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Nice.. are those the only uber hot spots when vmodding these? what about the mosfet on the top side which normally has a sink on it with the GTX flavor of the card? (I assume it's sinked, but it's hard to see under that hulking cooler - I know it's sinked on the 7800GTX with that smaller black sink)Quote:
Originally Posted by Shark-357
I´ve done some precision finger testing:D and found out that all of the IC´s except those three are running very cool.
But if i hold a finger on any of those three for more that 3-4 seconds it´s starting to really burn
Shark, ok - good to know. :)
to all: Hey - I found this pen
http://www.mgchemicals.com/products/8420p.html
and have to use this lookup page to find distributors:
http://www.mgchemicals.com/distributors/us/index.html
which might help others find one..
it lists off a ton of places near me in nor cal to call to see if they stock them:
http://www.mgchemicals.com/distribut...s_us_ca_n.html
Hope it helps! :)
I simply stated my opinion & never said I had proof. Don't get your panties all up in a bunch, gheez! I even stated that the VMem mod wasn't worth it, so just chill out.Quote:
Originally Posted by flytek
soz bud i think you're getting me wrong. saying things like that ^ on this forum is dangerous.Quote:
Originally Posted by CxP
unproven mods or theories for mods can and have recently resulted in some fairly serious hardware loss.
i just wanted to protect from any potential problems arising from your above statement.
please feel free to test your theory to the max and then let us know if you can get substantially lower than 555ohm on that resistor with a pencil.
I mean no disrespect or anything, but as I stated, I laid the lead on heavy. I don't think I could get any more on there. I don't think we'll get much lower resistance than around 550 using a pencil. But of couse, YMMV. Make sure you measure the resistance you are getting rather than rely on just my results.Quote:
Originally Posted by flytek
CxP
:fact:
ok i just tested this theory.Quote:
Originally Posted by CxP
resistence went down to 535 with a pencil alone easily
this yields about 2.30vmem
so anyone foolish enough to try pencil modding without a multimeter risks killing there card. :fact:
http://flytek.sa3doc.co.za/screens/7900gt/534.jpg
Quote:
Originally Posted by Shark-357
Thanks for the tip Shark. I put sinks on those three and the surrounding small ones too, what the heck I had time to do it and plenty of material.:D
lol good to know...i went down to 555ohms but i cant measure actual voltage for now..the vmem measure point is hard to reach :( did you measure it, that is how u know its around 2.3volts? damn xp-120 is in the way..i think i have to take the heatsink FAN off to get more leverage so i can get the probe into the "hole"Quote:
Originally Posted by flytek
but yah need a MM :D
604=2.00
575=2.10
555=2.20
234=+-2.3 (guessing)
i wouldn't turn the card on in this state so i didn't actually measure the voltage to the memory.
actually it appears that as the resistence on that changes lower the resulting output changes faster and faster so the vmem could be higher than 2.30
fyi - grabbed a conductive pen todat at Fry's in Sunnyvale, CA for $12.99. not too outragous.. I was expecting closer to $20.
Yeah same price as RadioShack as well for "CircuitWriter" pen.Quote:
Originally Posted by revenant
Guys I need your advice.
I did the 1.4 volt mod and 2.1 volt mem mod and was getting good speeds.
I installed power strip to see if I could push it further. Then the artifacts started happening. I dropped back the frequency, but artifacts continued. I was freaked. I removed the mods but they didnt disappear for 2 days, especially in Quake 4. The mem wont overclock so much now about 50 mhz less. Have I damaged the voltage reg or something?
Redid the mod on the GPU and all seems ok @650 but the mem wont take any extra volts at all. so its at 830. Ill be happy with that.
Resistor "J" replaced with 50 K0hm non variabel resistor.
With that mod + "his/my (#110)" will give up to 1.7 Vgpu
Im just wundering if it could be posible to do it like that :)?
Quite sure it is, but maybe I need to connect some of the points with a whire for the mod to work?
The picture shows a dibswitch, like that way of doing it more because I can change the voltages very easy :)
Going to do it to 2 grafic cards So it better work :p
i found this silverpaint pen on ebay, can this be used for the 1,4vmod ?
http://cgi.ebay.com/Electrically-Con...QQcmdZViewItem
Do I have to remove the 91C resistor to use pencil on it for switching frequency?
No you don´tQuote:
Originally Posted by Ening
is there a 1.6v or 1.7v conductive ink mod?
From what i've read it cant be done without removing & replacing the resistor with 50K ohms resistor. Also removing the 2 x OCP resistors shown in step 2.
http://sg.vr-zone.com/print.php?i=3330
So far 785 core with 1.55v conductive ink mod, just need some more volts :)
Thx
C-BuZz
785? Nice:clap:
My XFX (520/1500) just came today. Detect optimal comes out to 560/1660, and I havn't seen how far it can really go yet.
Might do a vmod sooner then I thought, and get a new heatsink for it.:fact:
w00t.. me also! got my cards today.. they're doing well so far.. detect opt freq ended up with 562/848 in SLI even, so I think they're a good pair. I am waiting to vmod until I get my zalman vf700s tomorrow.. damn these default fans are LOUD! I can't get over it.. lol. sounds like air escaping from a car tire! lol.
thx, i've done a run @ 800 core but was artifacting a bit. They scale a LOT better with negative temps :)Quote:
Originally Posted by Dr_at_Home
Can someone tell me if these are suitable?
http://www.dse.com.au/cgi-bin/dse.st...uct/View/R1903
Or this one?
http://www.jaycar.com.au/productView...Max=&SUBCATID=
C-BuZz
I use the one from dicksmith all the time. They are pretty good.Quote:
Originally Posted by C-BuZz
Excellent info, thank you t024484. Just a comment though:
85k+100kohm = 45,9kohm.
Will high switching frequency have any negative impact?
According to figure 21 of the regulator's datasheet (http://www.intersil.com/data/fn/fn9187.pdf), a 46k Ohm resistance for Rt will put the switching frequency close to 600 kHz (almost a 110% "overclock"). FET's can switch pretty fast, but if the high-side FETs for this circuit were not chosen with that sort of frequency in mind, they could get pretty damn hot. I'd keep an eye on it.Quote:
Originally Posted by t024484
The 85k resistor puts you at about 280 kHz. To be somewhat more conservative, I might try 70k as a substitute, which would take it to 360 kHz or so. You might still get the performance you're looking for while keeping the FETs cooler.
cheers,
sluggo
Just a tip. The easy way to do the voltage measurements is to solder 4" insulated wires to all the points of interest and dress them out past the end of the card. Attach a label to the free end of each wire with a note saying what it's for, and then just install the card into the chassis.
No poking around the back of a PC card with a long metal probes, and with alligator clips on your voltmeter leads you can even monitor the voltage while you stress the card.
sluggo