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SetiroN
12-27-2007, 12:00 PM
Hello everyone :)

Short version
Could anyone please read me his default resistors values around 8800GTX vmem mod?
Specifically the one involved in the mod and the ones of the same shape just next to it, making a quadrilateral with the solder point.

Long version
I've happened to get my hands over a supposedly broken 8800gtx, some guy tried to voltmod it with the result of fucking up the card memory and decided to give it away for just the shipment cost.
The card boots correctly, the "only" problem is everything on the screen looks totally messed up, freakin' colors running all over the screen.
Checking with a DMM, RAM voltage is around 1.2v...my conclusion is that this guy probably broke some SMD resistors while soldering the vddr mod.
So i tried modding the card myself (like shown in the above picture) to get the right voltage, but to reach 1.8-2.0v i have to use an unlikely low resistance, between 0.5/1.0 KOhm. When booting at 1.8+ volts, something starts to get readable on the screen, but most of it still showsoff in rainbow colors.
Most likely some of the RAM chips are definitely dead...but the thing i have to use such a low resistance to get the desired voltage gives me hope: maybe some more SMD resistors are now "resisting" less than they should and there still is a possibility to get the card back working.
That's why I'm now asking for your help: would anyone be so kind to read the values from a working card so i can try replacing them? :)

Thanks in advance to anyone who will, and forgive my grammar errors, English's not exacly my mother tongue :)


http://resources.vr-zone.com/Shamino/8800gtxvmod/2.jpg

SetiroN
12-29-2007, 07:20 AM
Anyone? :(

This is what i read right now:
1-3: 0
2-4: 0
5-7: 1.2K
6-8: 1.2K
1-7: 1.2K
2-8: 1.2k

http://www.setiron.com/8800vmem.jpg

tkpenalty
12-30-2007, 08:30 AM
Chances are, his voltmod completely damaged the memory modules so there is probably no hope of repairing it at all.

SetiroN
12-31-2007, 01:05 AM
I know, but you'll agree with me that it's worth a try.

PuMA
12-31-2007, 01:47 PM
those things are beyond hope when it come to repair. I mean they´re just hopless to get em running. i´ve tried many times and failed lol. thing is that u have so many things to consern (the circuitry might be fried inside the PCB if they use multiple layers, IC´s can be damaged very easily) but GL on ur project:toast::toast::toast:

fitseries3
01-02-2008, 08:35 PM
give me a day or two. im about to pull my gtx's and install the waterblocks on them. that'll be a perfect time to give you the readings. PM in a day or so.