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I just had another idea why the memories won't clock well: the copper plate is really really hot UNDER 3D (under 2D it's okay!). Perhaps the copper cooling plate produces that much heat, that the memories won't clock any further (kind of hot spot / heat accumulation). To confirm this idea, somebody would have to buy another cooler like that one:
http://www.maplin.co.uk/images/Full/47129i0.jpg
However then one has to find a solution for cooling the HSI Bridge...
There is another 7900GT 512MB card that uses the reference PCB shown here
http://www.itestate.com.au/products_...ode=PD00003810
Its made by Sparke and is called the Calibre, the web page is down ATM but it uses the 1.4 ram, same as the 256MB version so I would imagine its a lot better than the Gainward/Palit/XpertVision version of the card that OC's like a dog
The PCB looks identical so maybe the Vmods used on the 256MB version are the same
Page is up again http://www.calibrestyle.com.tw/main.asp
So U are saying that the mem isn't undervolted? Why the heck does it clock so poorly? I'd really like to get one of those but there's just too many question marks...Quote:
Originally Posted by persivore
Keep up the good works guys!
PS. Maybe they're planning to go with GLH version and that's why they messed up the mem here
hmmm. i like the look of the sparkle :D
anything 512mb on a new pcb would be worth testing
i'll try hunt one down. thanks alpha0ne
edit: @czuk - i actively cooled the ram and there was sufficient paste.
The memory is overvolted if anything. Its possible that the overvolting is reducing the overclock, but I wouldn't think it would decrease it to the extent thats being seen on these cards.Quote:
Originally Posted by toolboy
I wonder how it works with this one:
Gainward 7900GT 512mb Golden Sample Goes Like Hell edition 1.2ns DDR3 PCI-E
it says 580/1650 :confused: - mistake?
I've also seen one 7900GT 512 GLH on ebay.de and as far as I remember it was only 550/1400...
they've iether got a secret trick to hold the ram back or there are massive binning margins on these pcb's.
stock on the legends was 550/1400
Where the hell did my post above go ?
@flytek - have you tried underclocking the memory?
From what I've seen on other forums Gainward 7900 512 (at least quite a few of them) seems to have better 3DMarks results running 660-670 rather than the default 700MHz lol
The cooler has nothing to do with it, the PCI-E cards dont have a Artic Cooling Nv5 rev3 Silencer.
Cooling the ram doesnt help much , most of the heat is transferred via the PCB.
I have a Gainward 7800 GT 512 MB non-Glh with 1.4 ns Infineon Rams and in the beginning only 1200 Mhz were possible with 1.92 Volts .(the GLH uses 2.02 volts) . But with a new bios with reduced timings 1500 Mhz were possible und also a quite healthy gain in 3D Mark. So no speed binning , just a little less voltage and timings too tight.
I just received some hot information about the Gainward Bliss 7800GS+ card:
At the moment it is not possible to change fan speed in the card BIOS. Neither the defaults of 2D=20% and 3D=50% do work, nor the user made changes via Nibitor!!!
It's simple to validate that; change 3D speeds to 100% by using nibitor - you won't recognize any difference in noise level or airflow compared to 2D=20%.
Gainward says that Nvidia has prohibited external access (biossided.) on fan control.
All Gainward could do was changing the card ID, voltages and clocks. In the opinion of Gainward that step of Nvidia was necessary in order to ensure the reliability of the GPU.
Furthermore Gainward said that this is a common problem for many double-slot cooled graphics cards, that had a single-slot cooling solution in the beginning.
As a technical note I was able to obtain the information, that the fan isn't DC-controlled anymore but pulse width controlled.
Gainward already has adressed this issue to their design facillity in Taiwan. They hope that they will get a modified BIOS soon.
So, to clarifiy, has anyone compared the Goes Like Hell to the Golden Sample in any detail?
Do the PCBs differ? Are the bioses and timings any different? Are the voltages Different?
I assume it has higher core voltage as a start but why is it capable of higher memory on worse chips?
Is it likely to be deliberate or are there physical differences between the cards and this is just a side affect? Would flashing a golden sample with a glh bios mess it up?
I have a Golden sample coming soon as it was on a great offer, im keen to help crack this memory problem but i have no real experience with these things.
The person you spoke to at Gainward is, um, .... mistaken. Proof comes in the new ntune 5.0, which allows me to change the fan speed on my 7900GT to whatever I like.Quote:
Originally Posted by czuk
Note that this is controlled through a simple applet and no BIOS chage is required.
This 1.24V could be Vref, which is used as a comparison level for Data Input, CMD, and address signals. It is defined in the data sheet as as .7*Vddq, so if you are running your memory at 1.8V, then your Vref would be 1.26V. If this board is running it's memory at 2.0 Volts and the voltage you're looking at is indeed Vref, then there may be a problem.Quote:
Originally Posted by persivore
For a 2.0V Vddq, Vref should be at 1.4V. Usually a reference voltage like this is set through a simple voltage divider off of Vdd, so check some resistors around there and see if you can find one with 2.0V on one side and this 1.24V (or 1.4V) on the other.
Sorry to be a bit out of the loop in terms of electronics but if this is the Vref and its lower than it should be. What affect would this actually have? Does it cause instability at higher clocks? Thanks
My card should be coming today, i dont really have a motherboard to try it in at the moment but i might be able to use my dads.
Vref is critical. When the receiving circuits in the memory chip have to decide if the signal at their input is a 1 or a 0, it compares the signal to Vref. Any voltage above Vref is a 1, anything below Vref is a 0.Quote:
Originally Posted by Scarlet Infidel
If Vref is off by more than 2% of Vdd, then you are out of spec. If it's off by 5% ... who knows. If it's WAY off then your memory won't know 1 from 0 and you are utterly hosed. At what point it begins to affect overclocks is anyone's guess, but I think it's probably best to keep it within the 2% spec.
Yes i read up more on it, thanks for that info too. Basically if the vref turned out to be low is it because its been set too low deliberately, a design mistake (seems unlikely given its importance) or somethign else.
Would it be a case of simply increasing it or would this put a strain on other components. Basically is it likely to be set low or just not up to the job anyway.
Ive got my card now, i can test resistances till the cows come home but i have nothing to test it in for the time being for voltages and affects.
Honestly, I'd also have a hard time believing that it's a design mistake. It's too important and too easy to do correctly (so that Vref tracks Vdd automatically). On the other hand, this is the first time (to my knowlege) that OEM's are overvolting parts. I wouldn't be shocked to learn that something unexpected fell out as a result.Quote:
Originally Posted by Scarlet Infidel
If you trust the Samsung data sheet, Vref should be at 1.4 Volts. I don't know if setting it there is possible or if it is even the right thing to do. Samsung may have told nVidia that it's safe to overvolt Vdd but to leave Vref alone. I just don't know. All I can say is that it looks like a violation of the spec. Other than that it's all speculation.
I've sent a note about this to evga. I'll post here if I get a response.
Well as always, what they consider safe and what we do at our own risk are very different things. Im looking forward to their reply.
Its a shame theres not a little more activity on this thread, xtremesystems is always great at getting to the bottom of these things.
Would make sense to me that either vddq or vref (or both?) are a little off the specs...even the 512MB cards equipped with 1.2ns ram seem to hit a wall at around 1550Mhz although they should be quite capable of doing that speed.
So imho there's a general memory voltage problem with these cards...
Maybe i'm wrong...but shouldn't vddq always be half of vmem? :confused:
http://flytek.sa3doc.co.za/screens/7...persivore1.jpg
So if that 1.24V reading should in fact be vddq it's about 0.2v too high.
If anybody has an idea how to change that 1.24V (either up -for vref- or down -for vddq-) i'm willing to play the guinea pig as soon as my card returns from rma (got an already used one so i sent it back).
ok guys the solution to this little puzzle is to buy a sparkle calibre 7900gt 512mb.
the vreg design is the same as the 256mb 7900gt's and they should clock similarly.
i'm vmodding one within 48hours and will post results.
the core vmod is the same digital vmod as the 256mb cards and the 1.4ns memory seems to clock better than the legend/gainward style pcb's.
there will also be the same issue of risking burning the memory vreg if pushing the memory too hard.
I posted how I think the 1.24v voltage can be increased in post #86. Read a few of the posts above that one to see what I'm refering to in post 86.Quote:
Originally Posted by OneProdigy
Thanx, Persivore! I'll give it a try as soon as i have my card back.
Any idea on how to decrease that 1.24V?
Decreasing the resistance of the resistor above the 667ohm resistor should decrease the voltageQuote:
Originally Posted by OneProdigy
That would mean to desolder the resistor and add a higher rated one instead, right?
EDIT: I think i must have mixed up that 1/2 vmem thing with vtt, so nevermind. ;)
I have been very seriously thinking of buying the Calibre card for the last week but unfortunately they dont use the revised PCB (even though it is VERY minor), I'll make up my mind in the next day, otherwise it will be another MSI except VIVO and revised PCB :)Quote:
Originally Posted by flytek
The memory is spec'ed for 800MHz operation (1600MHz data rate), so saying that it should operate at 1550MHz is something I can't disagree with. However, it's not obvious to me that it's a voltage problem if the card's memory does not operate that fast. There could well be other problems that limit the data transfer rate, like some of the other timings set by the card's BIOS. I'm no expert on these timings, but my guess is they are just as critical here as they are for system memory.Quote:
Originally Posted by OneProdigy
Vref is supposed to track Vddq, so that if Vddq is increased then Vref should also increase. The ratio is not half, though. Vref is defined as .7*Vddq, so for a 2V Vddq, Vref should be at 1.4V. Cheers :)
So, glancing through the datsheet im going to summarise a few things, mainly for my sake.
....................Should Be .......................Measured
tRC.....................35........................ .........34
tRFC...................45......................... ........43
tRAS...................25......................... ........24
tRP.....................10........................ .........10
tRCDRD................12.......................... .......12
tRCDWR................8........................... ........8
tRRD....................8......................... ..........8
VDD.................1.9-2.1v......................... ~2.1v
VDDQ...............1.9-2.1v..........................not sure
VREF.............1.449-1.491v..................maybe 1.24v (for 2.1v VDD)
Sorry about the appalling formatting. It seems most things are within specifications except the timings are a little tight (shouldnt matter as they have set VDD at its maximum and the given timings are meant for 1600mhz anyway). This VREF definately needs more investigation.
The data sheet says VDDQ must be less than or equal to VDD (also should be between 1.9v and 2.1v as with the VDD), does it necessarily run at the same voltage?
Also VREF is 0.69-0.71 times VDDQ. Is seems that whilst the VDD is fine at 2.1v and the VREF is actually at 0.7 times the VDDQ as its meant to be just that the VDDQ is far below the VDD.
If the VREF is 1.24v then this divided by 0.71 (potentially) gives a VDDQ of 1.746v, is that what was measured at 1.74v? has anyone verified the assumption that the 1.74v was not DC as suspected?
I want to see someone raise their 1.24v in relation to their VDD. Then id be interested to see if 1, the memory clocks any better and 2 if the 1.74 or any other voltage changes.
OneProdigy if when you have your card you could measure the three voltages i have mentioned so i can see what your exact card reads. Thanks.
Edit: did anyone ever find more details about the NCP5424G. Ive looked over the datasheet for the NCP5424-D. Im not sure how it differs and what the suffixes actually mean.
Hey Scarlet - good data. Vddq is the voltage used to power the output drivers on the chip, while Vdd is used for the internal logic. The restriction that Vddq must be less than or equal to Vdd is there to prevent a condition called "latch-up", which can occur when a transistor is controlled by a voltage great than it's rail voltage.
MASSIVE EDIT: I keep forgetting we're talking about the BJ11/12 512MB part.
A Vdd or Vddq of 1.74V is not in the ball park for the 512MB part. The minimum voltage allowed (according to the data sheet) is 1.9V for both Vdd and Vddq. For the lower speed parts (BC14/16/20), 1.7V is the minimum, but that's not what this board uses, as far as I know. Please check the board for the part number suffix and correct me if I'm wrong.
The suffixes for the NCP5424 are just packaging fields. "D" is the standard part, "DG" is lead-free packaging,
So according to what sluggo said, Vddq shouldn't be the solution for the memory issue :(
I just don't get it, why a 1.2ns memory chip doesn't run at specified speeds even when voltages seems to be okay. :confused:
If it does help, one can find all kinds of datasheets at:
http://www.datasheetarchive.com/
I'm not sure if that's what I said ... at least, I don't think I'd claim that now. Vddq supplies the interface to the chip, and it may well be that the interface is the critical path. The memory cells may be clocking along with plenty of margin, but if the interface is not controlling the bus well, then the part still won't be a speed demon.Quote:
Originally Posted by czuk
Agree, the memory is not "being all that it can be". There are so many things that can create problems, though ... layout, clock integrity, clock skew .. it's a wonder it works at all. Consider that the memory does not drive the data lines between 0 and 2V to indicate 0's and 1's. The difference between a logical "high" and "low" is just .3V on these parts - just .15V on either side of Vref (trying to drive 2V transitions would take way more time, way more power, or both). With just 150mV of signal, the sensitivity to noise is very high.Quote:
Originally Posted by czuk
It's late and I'm starting to babble. I still haven't heard from evga on the clock_in skew situation, will post here when I do.
Well here in the UK its nice and early (in my terms) and ive finally got half an hour to play with this card. The 1.74v points on my card measure about 3.80v which pretty much confirms that they are PWM something or others. I dont have much longer but ill see what else i can find. My ram also seems to get 2.11v and wont clock higher than about 1560mhz.
If i'm lucky i should have it back by the end of this week.Quote:
Originally Posted by Scarlet Infidel
I'll report back with some voltage readings then...
results for the 512mb sparkle 7900gt: http://www.xtremesystems.org/forums/...d.php?t=101451
edit. a distributor erroneously sent me 2 more of the legend cards so i'll try a little more modding too :D
well this second batch of legends has infineon ram :(
it's rated at 700mhz and on these ones is clocked at 660 default
i hate it when manufacturers change specs after the launch batch.
the reviewers get the good stuff and the first customers too.
everyone gets excited and the bloody manufacturers despec the damn product, never tell anyone, and basically wind up scamming the masses.
infineon A
HYB18H512321AF-14
FVV14003
0552
http://www.infineon.com/cgi-bin/ifx/...geTypeId=17099
ggrrrrrrrrr........
From what I have seen of my friends Gainward BLISS GS+ 512MB, we took off his heatsink because of all the rumours about the "Yellow tape". At first b4 we took off the HSF I too thought that something had been left on acidentally... You can clearly see that there is some orange or yellow sumthing where the white thermal pad contacts the ram. But upon closer inspection.. I could easily see a cross-hatching pattern on the "tape" and instantly I was reminded of many thermal pads I've seen over the years..Quote:
Originally Posted by humeyboy
My opinion is that they used a combination of think, mushy thermal padding, and a layer of denser, thinner thermal padding. When we took off the HSF I was expecting to see yellow plastic backing tape, the kind you find on any pre applied thermal adhesive.. BGA ramsinks, MEMory heatspreaders, etc. This was not the case, and frankly I'm surprised that anyone would have thought that it was the backing tape..
We took some pics.. Lemme go resize then a bit and I'll throw them up here..
Here your go...
Pic #1
Pic #2
Pic #3
Make your own opinion I guess, but we left his on. I also can't see how that material could possibly block the GPU from contacting the copper.. as the pics show, the white mushy stuff had melted a bit, and i'm sure with some pressure that it would smush alot more... You can also see the size of the "tape", it's ultra thin..
Any I've been meaning to post some of these here for prolly a week or so, and now I have...
To me that is no better than fraud, I'd make a point of never buying there products ever again :mad: :slapass:Quote:
Originally Posted by flytek
Quote:
Originally Posted by kamakazibond
Many thanks for the pictures and your conclusion. I totally agree that this yellow stuff never was meant to be removed. You can actually feel, that it is kind of thermal material, as it feels quite cold imo.
What do you think about the black protective frames around gpu and bridge chip? Some users reported that the removal of these will give you a temperature advantage of roundabout 5°C.
Well thats a hard one.. We left his on, but thought about reseating it.. since the placement wasnt perfect and it bulged in one area around the GPU.Quote:
Originally Posted by czuk
I guess it depends on your own preference.. His temps are usually around the low 50's or so (from memory) so I dont think it is really an issue..
Those black "support" pads did remind me of my 9700 Pro's Metal shim I removed when Installing aftermarket HSF.. So I guess as long as your careful, you could remove them.. The argument I read was that they were holding heat in around the GPU and HSI. I'm sure thats possible.. but they also provide leveled support for the HSF not to crack the corner of the GPU or HSI, which the GPU and HSI remind me of Athlon 32bit chips, Which CAN crack.. ( I have a cracked corner on a 1800+ and IDK if I did it or not :eek: ).
So if your careful with it.. I suppose it couldn't Hurt, but I suppose you could also remove the majority of it, leaving only 4 small pieces in the corners for stability.. That would allow air to flow by and still keep the support around the GPU & HSI.
Quote:
Originally Posted by czuk
I'm one of them. Removed the frame and gained 5 C° (61>56).
But I think that the problem could also be on the original heatsink spring based fastening system. Maybe it can't apply appropriate pressure on the (foamy rubber) frame to 'squeeze' it enough.
Later I mounted a Zalman VF900 and pressure il a LOT more....it bends slightly the card. So maybe no reason to remove that frame if a good heatsink will take place of the original one (not bad but loud).
That very well could be, a sloution might be to take a razor and cut away most of it, only leaving the corners. That way it would require less pressure to push it onto the GPU as well as allowing air flow under there, while still giving the intended support.Quote:
Originally Posted by rOOk
I changed bios to 1.4 volt and i measure 1.4 volt
Could you please upload your bios-file, so that we could figure it out how you did it?Quote:
Originally Posted by Thomas
If you need a free upload service, try this one:
http://www.updownloadserver.de/
For the Pencil-Modders:
Attention!
You should measure the resistor value of the pencilled resistor (or GPU voltage) after a couple of weeks of use. We (german users) figured out, that it did DECREASE and thus, GPU voltage raise significantly!
On my card it was pencilled to 1.28V and now I it is 1.33V. Another user hat pencilled his card to 1.4V and now it was 1.6V!
Just validate your values again, as otherwise that will mean the end for the voltage ICs (and GPU of course).
Quote:
Originally Posted by czuk
yes, ...
4 days ago i had 1.71 Volt, now i have 1.75 Volt ! :eek:
... but, my card only do 750 / 1440 with 1.71 Volt < very bad results for this voltage i think ... -.- pff, and if the card goes RIP, ... i get a new one :)
P S :
have someone the v-mod for the VREF ??
... i will test it, if it could help to overclock the infineon 1.4ns memory better
So girls,
i have decreased the resistance of the contact obove the 667Ohm
http://img127.imageshack.us/img127/6787/lnregref5fs.jpg
639 Ohm > 1.24 Volt < VREF (695 MHz ram)
629 Ohm > 1.21 Volt < VREF (695 MHz ram)
617 Ohm > 1.19 Volt < VREF (695 MHz ram)
>> No Effect << ! :(
should i decrease the voltage more ?
... i thought that i have to increase the voltage and not to decrease
Scarlet Infidel, ...
i have decreased the resistance of the contact obove the 667Ohm,
(persivore said it on post #86 )
http://img274.imageshack.us/img274/4...sivore15iv.jpg
here the changes ... but 0 MHz plus :(
i dont know how to increase the voltage of the VREF ...
... h e l p ? :(
Im afraid we are at a loss on this one, it may just be imperfect design. I havent thought about this for a while but ill have another think.
Id recommend you return everything for normal if it isnt helping you, just to prevent it causing any damage.
Anyway, question time. Did lowering the resistance both decrease the 'VREF' and increase the 'VDDQ' on its own or have you changed anything else?
Now, if i remember correctly the one you refer to as VDDQ is actually something else which isnt even DC.
Also, exactly which card have you got? A Legend? We were mainly talking about the version with 1.2ns memory (or at least i was paying more attention because thats my version) but it seems the situation with the 1.4ns is the same.
i have only decreased the resistance of the part on post #86
and i have a gpu-voltage of 1.78 volt ... ya, i know that i am crazy x'D
i have a Colorful 7900 GT 512 MB Infineon 1.4 ns memory ...
tomorrow i will photography my card very sharp
lower resistance of the backside (part on post #86)
= lower VREF but more VDDQ voltage
... but all other voltages are the same like on your card ... like the VDD voltage with 2.1 volt
PS:
sorry for my english, but this forum is my last hope :(
Well we dont think the thing you measure as VDDQ is VDDQ at all.
I think we still suspect the voltage dropping on yours is VREF as you said. Im no expert at this im afraid, hopefully some of the pros will glance over this again and take interest in your findings.
Your English is fine. :)
i hope it also.
probably is the VDDQ voltage ( < what we think/thought) the VDD voltage
>.<
i really dont know
... but i know that our v-ram on the 7900gt 512mb is verly slow :)
tomorrow i will measure the other points on my card, good nite :)
Quote:
Originally Posted by MaSTeR-StyX
Any news so far?
i have penciled the resistor under the resistor on the backside of the card for the VREF ... but it dont help
today i will measure all the points and make some sharp pics.
sorry if smn posted this already, but is there anyway to vmod the core to 1.4V just using conductive ink?
It has been posted that often that I'm not going to explain it again. Just take your time and read this thread, it's somewhere on the first five pages.Quote:
Originally Posted by marauder16
You must not use conductive ink!!! Just a pencil. Read this thread...
thnx, I found it, but I'm still not sure if I should go with 512MB 7900GT, it seems they have many problems, 256MB 7900GT has an easy mod and no problems...
The CALIBRE 7900GT 512MB card uses the reference PCB so mods are the same as the 256MB card :)Quote:
Originally Posted by marauder16
7900gt 512 mb layout is the same like the 6800 GS 512 MB layout ?
hey, thzis is great, thnx man! :toast:Quote:
Originally Posted by alpha0ne
Hi guys and thanks for this great work, I'll do it very soon on my colorful ( and powerful ) 7900GT.
By the way, what about a Vmem Mod ? Did someone search for it, or find it ? My memory sucks at sock voltage ( 770Mhz :( ), I'm sure it'll help.
Thank you,
Kind regards,
Quentin.
I think somewhere in this thread there is a vmem pencil mod, try and find it...
I don't think so..
There is none.Quote:
Originally Posted by quent
GPU clocks are more important than mem clocks, so it's only a "small" issue.
There is a Vmem mod in posts 11 and 12, but it has little to no effect on the mem clocks from the tests that have been done.
I'm 99% sure that it is the correct mod for Vmem, as there are no other regulators on the card which could be used for Vmem regulation. There appears to be something else other than the Vmem voltage which is limiting the mem clocks.
I've attached a picture of how the Vmem mod can be done.
i cant see there a image
there is a different between VDDQ and v-mem voltage ...
i dont know :(
Theres a problem with attachments atm. I'll try to find the origional picture later and upload it.Quote:
Originally Posted by MaSTeR-StyX
Vddq is the voltage supply for the I/O buffers on the memory chips. On this card, it looks like Vdd (the voltage supply for the registers that store the data) and Vddq are tied together.
ya, but our mision is to increase the vdd and vddq voltage i think, because the VDDQ voltage is high enough :)
I'm pretty sure that Vdd and Vddq are electrically connected together on the card, so its not possible to increase Vdd and Vddq seperately. Using the Vmem mod to increase voltage should increase both Vdd and Vddq together.Quote:
Originally Posted by MaSTeR-StyX
Edit: I've attached a picture showing how to do the Vmem mod.
On my Xpertvision, the third resistor down from that long IC measures 2.62 kOhm. I penciled it down to 2.45 or so and on those points marked on the first page (GPU Vcore read and lower right of those 6 big soldering spots) it says I get 1.475 now.
Still, it doesn't solve my artifacting. I 'd like to try the switching frequency mod. Anyone knows how it's done on these cards? PLEASE!!
I dont think that the manipulation of the memory voltage does any good!
As we know from the 256 MB variety, the mem chips have vast reserves. The problem with the 512 MB Boards is probably due to timing inconsistencies of the RAM - the layout leads to corruption of the signals since the data paths have not exactly the same length. Reducing the CAS latency might help- it did a lot on my 7800 card with 512 MB. Reducing the latency by 1 or 2 might lead to much higher frequencies and better performance overall.
The best performance you should therefore see on the cards with the classic layout of the 256 MB type.
So, which of these is CAS latency?Quote:
Originally Posted by Doc Holiday
http://img138.imageshack.us/img138/9...ingset7od4.jpg
hay all i just got this card http://www.newegg.com/Product/Produc...82E16814130034
It's a 512 EVGA GT. I figure for $300 with 512 ram that can easy do 850 you cant go wrong. Now the VGPU mod shgould apply to this card? i havent seen anyone with it yet...
speaking from experience pin 6 is not ground.
http://homepage.ntlworld.com/adam.ne...2mb7900gtR.jpg
Do these mods apply to calibre 512 7900GT also ?
:D
no the calibre has the standard digital paint mod that the reference nvidia 7900GT's have.
you will notice the calibre pcb is completely different to these red 512mb cards.
Is there now a solution for a VGPU mod concerning the new Layout Palit / Xpertvision 7900GT 512 MB?
Messuring at the former VGPU Point I got 1,4V which is barely enogh for 580MHz, even with a Zalman VF900 ;)
mfg aLVaMaN
welcome aLVaMaN - you got some pics of ths new layout? :)
I am sorry, I was not able to login the last days.Quote:
Originally Posted by flytek
http://img455.imageshack.us/img455/2...t512mb1sa5.jpg
The picture shows a Palit / Xpertvision 7900GT 512MB with new Layout.
mfg aLVaMaN
I started to messure the important points. VGPU is probably found (1,29V), as the card does only 580MHz GPU clock.
http://img524.imageshack.us/img524/4...voltagead4.jpg
Does anybody know how to messure the small resistors? I do not get any correct values :slapass:
Regards (in German mfg) aLVaMaN
Thx for measuring, aLVaMaN :)
Has anybody got an idea where to begin? A lot of people are waiting for a Palit Volt mod. ;)
http://i68.photobucket.com/albums/i2...tfullfront.jpg
http://i68.photobucket.com/albums/i2...gtfullback.jpg
For comparision: 7900GS 256 from Palit:
http://139.18.42.44/~pete/tmp/vmod_2.jpg
Looking quite similar...
Could you do a close-up of the other side? Especially the area near the power connector.Quote:
Originally Posted by dracoonpit
Regards aLVaMaN
I was finally able to measure that small resistors;
http://img98.imageshack.us/img98/895...sistorsil2.jpg
Regards, aLVaMaN
are those measurements from the indicated points to groung?
i think you need to measure the resisters themselves by probing both sides of each one while system is off.
i think the black ones are more likely targets and that is only if the central IC there is the vgpu regulator
Hello from Germany,
here is a picture from my Palit 7900GS PCI-E 256 MB.
You can see the voltage area clearly i think.
http://img109.imageshack.us/img109/2...0625xv4.th.jpg
Alle measurements ar taken from the points to ground.Quote:
Originally Posted by flytek
I think it should be clear that the targetted IC is responsible for VGPU. Compared with the former standard 7900GT layout there is imho no other chip at all which could do that AND is not responsible for other voltages required.
persivore suggested to connect a 10k variable resistor between one of the red points measuring 626ohms and ground. So why measure the resistances of the resistors themselves as they are (imho) not important in this case?
Do you mean the black ones with three legs?
aLVaMaN
Could it be that our IC is on the back side of the card to control the voltage?
...
There are three on the back. One is for VMem, one for VDDQ and the third one is out of range...Quote:
Originally Posted by KGB44
Furthermore VGPU can be measured next to this IC on the front.
Should we do a vmem mod first? :stick: ...
i think we need more time for a vgpu mod. Our gods for vgpu and vmem mods (the xtremesystems members) can't help us i think :p: :eek:
hehe...no...i recommend whatever persivore recommends :DQuote:
Originally Posted by aLVaMaN
i agree that this IC is 99% the one for vgpu but i can't be sure cause i'm a lay man in these things.
the only reason i figured to measure the value of the little black SMD's (not the 3 legged ones) is that once you know their resistence you will be able to adjust said resistence accurately with a pencil (say 2.5-5% adjustment)
once you have found the one that raise your vgpu/overclock then soldering is possible with more accurate knowledge.
but that is only what i would do because i know so little.
follow persivore's advice imo or ask him to comment on the pencil idea to help try confirm the correct point.
well done on getting this far :)
it seems that success is much closer now.
Ah, now I know what you´re getting at! The pencil method seems to be a nice chance of not hurting anything. I´ll give it a try after aksing persivore.Quote:
Originally Posted by flytek
Indeed!
And Layout of the Palit GT and GS seems to be identical too.
Any new here? :confused: :slobber:
It is getting concrete now.Quote:
Originally Posted by KGB44
I will try it tomorrow :)
Regards, aLVaMaN
Mod is working ;)
On 600 OHM's, i reached 621MHZ + 40MHZ Geo Clock...
http://img85.imageshack.us/img85/986...00gsdq7.th.jpg
Without any modifications you will mesure ~ 626 OHM's or a little bit more. You must reduce the Resistor until you mesure ~ 600 OHM's or something. You need only a fine and sharp pencil and 10 minutes time =)
Get my card from:
584 MHZ GPU Clock + 40 MHZ Geo Clock
to
621 MHZ GPU Clock + 40 MHZ Geo Clock
My Card is not one degree hotter than before - i think this is only ~ 0,025V more or something, can't mesure the voltage becouse my card is in my PC :p:
Thanks to shamino from vr-zone.com and Alvaman - they gave the tip about that and i tested =D
I can confirm that this mod works on the 256mb Xpertvision 7900GS :)
I shaded the resistor down to 595ohms and I now get 1.42v in 3D.
That gets my clock up to 695 :)
Am still having probs with my mem tho - can get it to 725 now. Must be something else holding that back. Anyone got any ideas?
bb
But now ... we need a VMEM Mod, becouse the Palit Cards are using Infineon RAM with a standard voltage of 1,8V (!) not like the other cards with Hynix RAM @ 2,0V.