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twisted1
09-22-2014, 09:33 AM
Firstly you need one 8800GTX, ref. card.
http://i919.photobucket.com/albums/ad33/thereal_twisted/8800GTX/IMG_20130804_222448_zpsbd7abb30.jpg (http://s919.photobucket.com/user/thereal_twisted/media/8800GTX/IMG_20130804_222448_zpsbd7abb30.jpg.html)

I've delidded my cards, it drops the temps quite a bit.
http://i919.photobucket.com/albums/ad33/thereal_twisted/8800GTX/IMG_20140826_203455_zpseeaf8wtr.jpg (http://s919.photobucket.com/user/thereal_twisted/media/8800GTX/IMG_20140826_203455_zpseeaf8wtr.jpg.html)

For VRM/VRAM cooling I just used a hacksaw and adjusted the stock cold plate so the waterblock would fit.
http://i919.photobucket.com/albums/ad33/thereal_twisted/8800GTX/IMG_20140826_203410_zpsxim6h6bk.jpg (http://s919.photobucket.com/user/thereal_twisted/media/8800GTX/IMG_20140826_203410_zpsxim6h6bk.jpg.html)

http://i919.photobucket.com/albums/ad33/thereal_twisted/8800GTX/IMG_20140922_022650_zpsqonzpqsn.jpg (http://s919.photobucket.com/user/thereal_twisted/media/8800GTX/IMG_20140922_022650_zpsqonzpqsn.jpg.html)

I'm using watercools VGA blocks, they're great when you run SLI(I have another one that I will be modding too)
http://i919.photobucket.com/albums/ad33/thereal_twisted/8800GTX/IMG_20140922_022743_zpsfq2tsr45.jpg (http://s919.photobucket.com/user/thereal_twisted/media/8800GTX/IMG_20140922_022743_zpsfq2tsr45.jpg.html)

The black wire from the 500ohm trim pot. that connects to the primaron controller.
http://i919.photobucket.com/albums/ad33/thereal_twisted/8800GTX/IMG_20140921_204221_zpsuf7zy5i0.jpg (http://s919.photobucket.com/user/thereal_twisted/media/8800GTX/IMG_20140921_204221_zpsuf7zy5i0.jpg.html)

Overview, the cables that connect to the molex are, from the left to the right Vgpu, Vmem, Ground.
http://i919.photobucket.com/albums/ad33/thereal_twisted/8800GTX/IMG_20140921_231952_zpswpok4dt5.jpg (http://s919.photobucket.com/user/thereal_twisted/media/8800GTX/IMG_20140921_231952_zpswpok4dt5.jpg.html)

And a pic of it ready for take off. The VRM's get hotter when you give it 1.45V :D So a fan is probably a good idea.

http://i919.photobucket.com/albums/ad33/thereal_twisted/8800GTX/IMG_20140922_024920_zpsrkiwg74j.jpg (http://s919.photobucket.com/user/thereal_twisted/media/8800GTX/IMG_20140922_024920_zpsrkiwg74j.jpg.html)


I don't have to much results to show off, but absolute max before was 702Mhz gpu, now it'll do 730Mhz after that I'm hitting OCP. Got the SMD's needed for removing OCP though will get to that soon.

Another issue I had was the massive Vdroop, I could set it to 1.4V and under load running 3dm06, it would drop to 1330mV. And the voltages where just very unstable. I think I need to add some caps or something like that, I have 2 dead 8800GTX that I can take components from.

Anyone got any experience with cap mods? Will the caps from my dead cards be fine or should I use something else?

twisted1
09-22-2014, 11:44 AM
Turns out that the so needed OCP mod will take care of the vdroop also. Those little smd's that you solder on the card for the OCP mod, they are sooooo tiny. Wish me luck :D

Arne Saknussemm
09-22-2014, 05:58 PM
Will the caps from my dead cards be fine or should I use something else?

I have this cap?

41412

:D

Good luck...you nutter!!

Love it!

twisted1
09-22-2014, 06:30 PM
I have this cap?

41412

:D

Good luck...you nutter!!

Love it!

These cards can go well above 800Mhz with Vmod and OCP mod, right now OCP is capping me at around 730Mhz.

OCP mod involves soldering small SMD's on top of existing ones. Just to give you an idea of how small these smd's are. Here's one laying on top of a mem chip on a 8800GTX. It's that small thing with 122 on it :P

41414

Menthol
09-23-2014, 11:00 PM
Glad you got SMD's, not STD's

After you get this done, I have some 980's that need modded, my eye sight won't let me do it

twisted1
09-23-2014, 11:09 PM
Glad you got SMD's, not STD's

After you get this done, I have some 980's that need modded, my eye sight won't let me do it

lol, really don't wan't STD :)

Hehe, yeah I saw zombie mods for 980, sweet :)

Got the SMD's soldered on there now, fingers crossed it works.

Menthol
09-24-2014, 12:35 AM
One thing you can count on is support from your buddies here. I wish you good results, I have an 8800 if you need one

twisted1
09-24-2014, 08:01 AM
One thing you can count on is support from your buddies here. I wish you good results, I have an 8800 if you need one

Thanks Menthol!

I've got it up to 730mhz stable now, can run kombustor @790mhz but not in benches, yet.

I got four 8800gtx, two that are alive. The others are donor cards. I got a box full of dead vga, lol