280 gtx volt mod VDD & VDDQ

[Threedhero]

Anyone use the 280 gtx VDD and/or the VDDQ mods for this card? Not sure what they are or what they control. What would safe voltage be for these on DICE?

Any insight would be helpful.

[K404]

For the Hynix RAM used, I got my best results at ~2.21v.... I found that it doesn't scale much with volts and doesn't like high voltage.

 

vCore..... I suspect you'll tune vCore to stay within OCP. OCP mod is important for these cards.

 

There's also a balancing act to be done between GDDR and core MHz. The memory MHz you get during pretesting on air will *probably* have to be reduced in order to max out the core under LN2 (or dice.)

 

Sorry.... I don't have voltmod pics for these cards. Someone else will be able to help for sure though

Edited June 24, 2013 by K404

[der8auer]

Here you go:

 

 

 

 

[Threedhero]

Thanks guys most helpful!

 

But what is the VDD and VDDQ for and what are safe volts for these?

[CL3P20]

vddr and vddrq are RAM voltage and termination/driving voltage..

 

vDDR is needed for speed increases..

vDDRq can help stabilize IMC at high RAM speeds.. like VTT/Aux voltage on ATI

 

vDDRq was good for me on 285 with +.15v only.. more did not help me hold higher speeds under -0.. I think cold helped the mem more.. but when your squeezing for every mhz..

[xxbassplayerxx]

Reference 280 can have voltage changed with software, but the OCP mod did nothing for me.

[der8auer]

Usually you dont need much voltage anyway. The G200 GPUs scale a lot more on temperature than voltage.

[Threedhero]

Thanks again everyone great advice, hope to bench within the next few days.

[xxbassplayerxx]

If I recall, I only needed about 1.30V-1.35V. Didn't get any good scores but I kept running into OCP.