9500gt Ocp

[lism]

I heard there's a 9500GT OCP going on, (Overclock protection). At certain speeds it just locks up, no matter how you put your voltage, even up to 1.6V the card still refuses to accept a speed above 733MHz.

Any documentation?

We're playing in a contest together with more then 25+ contestants at several sites (all Sparkle 9500GT 512MB DDR2). I have'nt even recieved the card and people complain already about lockups caused by Nvdia's OCP.

[ceemic]

Has someone tried to modify the BIOS for example with nibitor?

[lism]

I'm not sure, but by opening an Asus 9500Gt bios with 512MB DDR2 memory does'nt look like there's an OCP-thing in the bios itself. From what I heard some things needs to be soldered in order to bypass the OCP, like flash your card at a higher clock, so the OCP has a longer value after flashed.

[largon]

What do you mean "the card still refuses to accept a speed above 733MHz"? It crashes immediately if you set the clock even in idle? Or is just generally unstable in 3D load? Or does it crash as soon as it goes under 3D load?

PS.
"OCP" = overcurrent protection.

[lism]

Whoops, lets make it an OverclockProtection. Whenever you hit 750MHz with the core, even tho the voltage is at 1.3V or wether 1.4V, the card chrashes. Just instant BSOD. Some of us figured out there needs to be soldering on one of the transistors with some variable resistors in order to make it work again. But there's is'nt much documentation about this yet.

[lism]

*Kick.

The OCP is a pain in the ass :( Vapochill is ready but if i cant get pass 730MHz my vapo is'nt much of a help.

[ceemic]

Try other BIOSes from different 9500GT-s. Just make sure they use same mem chips!

[lism]

Bois fails to flash, some warning message. Hate to destroy my card.
But, At page 11 of http://www.anpec.com.tw/ashx_prod_file.ashx?file_path=20080916142605265.pd f&original_name=APW7065.pdf ,, there's detailled information about the triggering whenever the Clocks hits too high. Can someone pintpoint out how to bypass it?

[Diegis0n]

As i also participate in the contest, i'll be needed the OCP too :D

There are 85 participants by the way ...

Edit: Bios flash isn't working here either

[nigelke]

same here :)

i wil check it out myself and post my findings here :)
Also about that bios flash thats somthing othere participants found out to :D it does not work xD


edit,
after looking at the datasheet i think the answer lies with the lower mosfet's. I think the trik wil be to find this one and making sure that voltage there stays at a certain point. But thats for this weekend :p

[Diegis0n]

Keep us informed :up:

[nigelke]

wil do ;)

Its a pitty that the person who already solved this problem doesnt seem to like sharing it :)
I can understand him but its just a game :p :D ore at least thats my opinion :)

Now lets have a look at the card with the datasheet ^^


the chip is => APW7067
but the data sheet is about the APW7065
http://pdf1.alldatasheet.com/datasheet-pdf/view/149563/ANPEC/APW7067NKE-TRL.html
thats the correct one ;)

edit,
i was looking at the VGDDR it has OCP aswel lolz :D
my mistake :D

[lism]

Replace the 6 mosfets with a lower RDson. Or, cool the mosfets down on a extreme way so the resistance stays low and therefore you can overclock a little higher.

Using a vapochill on the card (pics below) did'nt really made a difference. It's not really the OCP thats kicking in, rather a strange way of overclocking and often have different values, keep lower GPU core and have higher shaders, or keep all things low in order to gain higher memory speed. It's so abnormal to overclock with this card. 320+ FPS in nature was the number 1 spot.

http://tweakers.net/ext/f/EtIFuYJOnTDEYAY3aZ1V5aHK/thumb.jpg (http://tweakers.net/ext/f/EtIFuYJOnTDEYAY3aZ1V5aHK/full.jpg)

(Click, vapochill XE at -31). The memory is also a pain in the ass. Does not like higher voltage, does not even overclock at all that much (400 > 631 max)