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I have read this thread and numerous others on the web.Quote:
Originally Posted by t024484
My question is posed because of conflicting information, and I appreciate knowledge from other people who have tried it.
I note your detailed image, but if it WAS perfectly clear I wouldn't be posting a question now...
Please and thank you. :slapass:
What exactly is conflicting, and what is not perfectly clear?Quote:
Originally Posted by xit
crap. I think I worked it out.Quote:
Originally Posted by t024484
Soz. I was confused by the references to 1.7v, but now realise it is if the 5k resistor is in place only.
Hmm, I have a wierd problem. I got a new 7900GT to play with, and so far it doesn't seem to be as good as my first one. The core goes high, but the memory won't go passed 830 or so.
Ok, the problem is, my resister labeled "K" in the first post of this thread, seems to not be working. I checked it with my meter, and there is nothing there. I made sure I cleaned both solder pads at each end of the resistor incase there was some film on there keeping me from getting good contact. Still nothing at all.
So what kind of problems could this cause?
Also, I checked the voltage to my memory and it seems to be at .800v. I know that can't be right, but i'm pretty sure I checked it at the right place. I shaded the resistor to up the vmem like the vrzone site says, and checked again at still .800 and the memory didn't seem to overclock anymore than before.
The card will run 730/830 with a 40mhz delta pretty well, but the scores are low compared to my other card. I only get around 11,200 or so in 3dmark05.
If you guys have any ideas I would appreciate them.
Thanks,
Marlon
Sorry for repeating the question, but to increase the delta, do I have to use pencil on the condusting place on the left side from resistor K?
If you are talking about the geometric delta clock, then no, you can't shade a resistor to change that. It has to be changed in the bios of the card.Quote:
Originally Posted by Ening
If your talking about another delta, then I'm not sure what you are talking about.
Marlon
I definatly think your card is bottlenecked by the CPU. My first card scores 6750 in 3dmark06 at 724/921.Quote:
Originally Posted by C-BuZz
http://service.futuremark.com/compare?3dm06=229525
I only have a higher score than you because my CPU score is so much higher. Your FPS and SM 2.0 and 3.0 score are better than mine. With a better CPU your scores would ROCKET!!
Marlon
Whoops. Sorry. I meant this mod for switching frequency:Quote:
Originally Posted by snakeskinner
I don't know why I wrote "geometrical delta". But what about switching frequency, is that place to the left?Quote:
And than comes a very important Mod, being resistor K.
This resistor measures ca 80Kohm, and sets the switching frequency.
Connecting a 100Kohm resistor in parallel, almost doubles the switching frequency, and solved my problems completely.
You could eventually do this mod by pencil, try to get the value down to approx. 45Kohm.
Sorry for noob question.
um that's entirely clear in the post.
measure the resister in question and adjust your probe orientation till you see 80kohm as the default value.
then pencil over the top of the resistor till the provbes, using the same orientation, reads 45kohm.
pencil dust is not very reliable a conducter so try blow any loose carbon far away from any part of your card and default to a higher value.
i find that resistence can move based or things like humidity or temperature so to be safe rather aim for 55kohm with the pencil.
if you go to low like 30kohm first blow as much off as possible and then touch the pencil mark with say your finger to remove some dust.
you should quickly see just how dicy and unstable pencil modding really is.
i don't think it's a viable long term solution.
for a quick bench ok fine but be carefull and don't expect the value to remain where you set it initially.
it would be wise to check a pencilled resister every day before starting a rig or measuring the resultant outpu regularly so voltage output creep can be noticed before it becomes deadly.
I read this thread a few times over and decided to go for it myself. I ended up doing this. I thought I was going to get 1.4Vgpu, but ended up with 1.5Vgpu, not to mention the core will run up to 725mhz from 570 on stock volts. Any ideas?
Edit: Idles @ 44C / Load @ 62C. Zalman VF-900. Ambient of 24-26C.
What do you need ideas about? That is the mod for 1.5v. If you only wanted 1.4v you should only have grounded D511. If your max load is 62 then you're fine, but I wouldn't go much further without better cooling. Have you done any real stess testing to verify that 725 is stable? Mainly: have you run ATItool (version 0.24 beta 14 which works with nVidia cards) and run the artifact scanner to verify you're not overclocking too high? Run the scanner for a good 25min and if you get no artifacts you're good to go. Atleast, that's how long I run it for to be sure because I've had zero artifacts for 10min only to have em show up a min later like crazy.
Some good (i suppose) & bad news.
Bad news, card is dead.. for now :)
Good news is dont use 1.85v on the core :slapass: Now ya know.
The chip circled bottom left (attatched pic) caught fire... literally, & went up in smoke when I turned pc on. I need some info on what type of chip it is. I cant tell what type of chip it is as it's all charred & burnt. If someone could take a close up & provide some information on it be much appreciated :)
Chip has been removed & i'll try source a replacement to see if I bring her back from the dead..
Thanks
C-BuZz
I just want a solder mod :(Quote:
Originally Posted by Nosfer@tu
I dont give a rats ass about my RMA posebilityes. Just want a good old fasion Variabol resistor on GPU and VMEM, :( Help???
Look one post above yoursQuote:
Originally Posted by Nosfer@tu
Imossible unless you only want max 0.05-0.07v increase, if so see the first two pages of this threadQuote:
Originally Posted by Nosfer@tu
That chip is not for the vgpu at all, it is for vmem. I think it would be impossible for that chip to burn up by doing the vgpu mod though I've been wrong one time before in my life :PQuote:
Originally Posted by C-BuZz
Can you describe the mod you did in more detail/pictures?
See this thread for info, I'm sorry it will not get your hopes up very much though...
http://www.xtremesystems.org/forums/...ad.php?t=96983
what were you running your memory voltage at please.Quote:
Originally Posted by C-BuZz
we need to figure out what vmem is safe for 24/7.
The numbers on the chip areQuote:
Originally Posted by C-BuZz
4420
BA6C13
The burned component is a N Mosfet.Quote:
Originally Posted by C-BuZz
It is used by the Vmem switching regulator as one of the two switches.
One is connected to ground and the other to V+.
The one that is burned on your board is connected to V+.
To burn out such a Mosfet means that both Mosfets are conducting at the same time, which in turn means that the voltage regulator was not functioning properly.
May be you have increased Vmem by lowering the value of a resistor, and maybe a short cicuit occured.
Anyhow, you will have to replace both Mosfet's, remove the extra resistor that increased Vmem and hope that everything is still working.
What you need are two N Mosfets with a channel resistance of 10mOhm or less, a max current of 100 Amp and a continous power of several watt.
The housing is a SO-8, but other housings can be used also.
An example is the IRF7821.
sorry - quoted this again.. but)Quote:
Originally Posted by C-BuZz
DOH! that suuuuuuuuucks. sorry to hear about this. that's one of the chips that poeple sink because of over-heating issues with these vmods. That one and the one to the right and up just a tad..
Thx for answering me. I have 2 7900 GT awaiting modding and a few more comming in next week.Quote:
Originally Posted by Per Hansson
I just though that when "Resistor "J" was replaced with 50 K0hm non variabel resistor" the Shamino mod would be posible aswell??????
But gees not.
BUT IT SUX!!! So when benching you have to remove your card and redo the conductive ink :( :banana::banana::banana::banana: :(
Thx all for your input.Quote:
Originally Posted by t024484
I did not touch Vmem @ all & I had no vmem mods other than pencil mod in place. Only thing I increased was the Vcore. Please point out the second mosfet that needs replacing.
The mofset has a small metal pad underneath it, whith 6 contact points (contact points where underneath the metal pad connected to the pcb) the metal pad came off with the chip. Which was connected the the unburnt pins. What purpose do they serve?
In the first pic the contact point on the first pin seems to have completely burnt out? Anything I can do about that? Or just pray it still makes contact?
I did not notice any other burnt out chips, only the 1.
Thanks again :)
C-BuZz
Cant find the IRLR7821 N Mofset anywhere local :(
I have 2 big electronics stores close buy but not to sure which Mofset I could use as a replacement.
http://www.jaycar.com.au/ or
http://www.dse.com.au/
Can someone please point out a suitable replacement Mosfet. I can handle soldering one like this on no probs :)
http://www.xtremesystems.org/forums/...9&postcount=38
Thanks
C-BuZz
you don't have to use conductive ink, and you don't have to redo your mod everytime you want new voltage. you can use switches between the mod points and ground to toggle the +.05v, +.1v, and +.2v aswell as a switch to toggle between the 5k resistor and 50k resistor to toggle the base voltage between 1.2v and 1.5v. Doing so lets you adjust from 1.2v to 1.85v in .05v increments (though going higher than 1.7v is risky with any cooler and you'd need to adjust overcurrent protection to go over 1.7v)Quote:
Originally Posted by Nosfer@tu
Here's how you'd use a switch to toggle 5k and 50k:
http://www.xtremesystems.org/forums/...1&d=1146359748
Here's a breakdown of the different groundable points if you want to use a dip
switch.http://www.xtremesystems.org/forums/...1&d=1146356347
One thing is for absolute sure!
Do NOT overclock these card without adding a stick-on heatsink to those 2 chips that get boiling hot. So hot that is clear the they melted the solder off one members card and the chip fell off! Crazy.
Im using a copper stick-on heatsink and still it gets hot but not hot enough to damage anything.
Anyway, I did the 100k mod with the 1.7v core mod and it screwed everthing up. The card flashed video on and off and on and off. :(
I pulled the 100k resistor off and reverted back to 1.5v core and now the card does not overclock as high as it used to. :(
100K resistor? It's supposed to be a 50K. Was it two 100K in parrallel or a 100K variable or did you simply use one 100k resistor? Also, did you try 1.55, 1.6, etc first or did you jump straight to 1.7? what kind of cooling are you using?