RE: overclocking 7900gt and stability

[Crash425]

So I bought myself a new computer and couldn't pass up an evga 79000gt refurb for $202.

I've heard all sorts about the instability of the card on the ram front, but also how great it can be as an overclocker. Since its a refurb, presumably it has the ram issues, or has had them.

My plan is this, I'm going to conservatively downclock the ram, and overclock the gpu. I have a zalman VF9000 waitin in the wings for it.

How do you feel about this plan? Will underclocking the ram affect my performance severely?

Also is underclocking the ram a viable fix for the problems with this card? (evga already underclocked it back to stock with the refurb.)

Thanks in advance for your help =).

 

[burn-e86]

dont bother, i remember reading on a review (cant remember where, might have been here though) that the RAM runs stock at 800mhz, which means that its running underclocked anyway, i overclocked mine with the stock cooler and it was only 2~3 dgrees warmer. i bench marked it with 3dmark (sod off ppl who say its not "real world" doenst matter, only has to prove a point) and got 30% more performance from 03, around 20% for 05 and 14% from 06.

 

[illinikevin]

I just overclocked mine until I started seeing artifacts in the games I played and then backed it off some till they went away. I never had a problem with heat I just went to the zalman cooler to reduce noise.

 

[Dissolved]

I have my eVGA 7900GT KO overclocked to 580MHz on the core and 800MHz (1600 eff) on the ram. The ram is capped off at 1600 so you can't go any higher than that (as far as I know). One thing I have noticed though is that it sucks a lot of power when you OC these cards. I have a 480W-12@18A and had to order a 560W-12V@38A so hopefully now it will be able to go higher. I read on some forums people putting their 7900GTs up to GTX speeds on the core with a little volt modding but supposedly it can be done.

 

[david_uk]

by taking a soldering iron to it, apparently.

 

[burn-e86]

i dont think it's capped at 800, i if i remember the RAM is rate'd at 816Mhz it's just that it cant handdle more then 800 on most cases
http://forums.extremeoverclocking.com/showthread.php?t=216265 for volt modding

 

[darkstar782]

Taking my Gainward 7900GT card from 550/1400 to 740/1400 yielded a ~18% 3dmark06 score increase, for a 34% GPU speed increase, so I'd say these are memory limited to an extent.

 

[ike2187]

for the gpu volt mod you only need a conductive pen. You can get better memory speeds with the pencil mod. I have a the new reloaded version from evga and the memory wouldnt get past 780 without any artifacts. But with simple voltage increase I got it up to 870 but ive seen people get to that speed without any mod which makes me think my memory sucks.

 

[darkstar782]

My gainward card is not a reference board layout, and the Vcore is done with a pencil mod.

Havent touched the RAM yet, thats a pencil mod too on this card, We'll see how it goes.