8800gts g80 OCP/OVP?

[Calathea]

Hi!

Got a 8800gts 320 that makes 756/1674/1050 on 1.40/2.10 volt. Problem is, when raising clocks even a little, in riva from 756->783 (smallest step) benchmarks starts to crash. It's rock solid at 756MHz, full load ~35C on cold water. I've done the ovp/ocp mods described in an old thread here at XS, but doesn't help. Before mods the driver stopped responding, now the srcreen starts to flicker and eventually it will freeze. No change in max OC.
This is what I've done: Three 1k reistors in parallell with smd-caps,(supposedly the OCP mod) and pencil the resistor "70B" to about 4,7-4,8k from 5,2.

Tried up to 1.6 vgpu and pencil 70B down to 4.3k. No difference!

[K404]

IMHO its not really an OCP/OVP problem... its just the normal stop point of the G80 cards on water. You taking the volts up to 1.6v pretty much confirms that From your MHz, im guessing its an A3 core

OCP and OVP arent so important for you at the moment... I would say the most important thing you can do is mod to control vDroop, which I bet will be losing you around 0.06v under load and will be why you need 1.4v for the MHz you have

After that, the most important thing you can improve is your temps.... ie... freeze it, if you want more MHz

[cowie]

yeah freeze it
i go 756 on an A2 stock volts -35c a3 790 stock volts -35(gts320 or gts640 it dont matter)

[Calathea]

The card has an A2 core, so I guess I should be happy with the clocks right now. I'm just not used to such a "hard wall" on a graphics card. Will take a look on vdroop. Thanks!

[CryptiK]

Soldering the resistors in parallel with the caps should also be reducing your droop under load to around 0.02v, but confirm that with a DMM. Great clocks for an A2 btw.

[Calathea]

My DMM can't dispaly more than 2 digits :/ Anyway, 1.40V 2d is 1.39V in 3d06. I doubt a smaller vdroop will gain me 30MHz or more, so I won't push this card further. Have to focus on cpu instead

[K404]

Thats pretty decent for A2!

Also.. nice work on the vDroop