anyone OC'd gtx275's core over 740mhz??

[grishenko45]

if you have - please tell me what brand and edition - i was going to go for the XFX GT 275 XXX edition which has a slight OC on the core only, from 633 to 670mhz, ive heard they only go to 720-730Mhz. I want to be able to push one just over 740Mhz (so over 100Mhz over stock - thats what I got for on all cards!)

thanks all

[Amtrak]

First and foremost, you must understand that every card will be different. Unless you get one pre-overclocked to your desired level, you can never assume that any card will be stable at a given clock speed (and even then you hear of some people getting unstable factory-overclocked cards).

I purchased EVGA's stock-clocked GTX 275, but as is often the case with EVGA, the card I received was really an unmarked Superclocked edition (648 core/1458 shader/1188 memory). My particular card is just stable enough to be benchable at 771/1584/1332 (actual clocks as reported by EVGA Precision), but seems to be extremely stable at 756/1566/1296 (also actual clocks, although I'm still testing with it). I think my core overclocks a lot better than many others with this card, but then again I haven't seen very many for comparison. I was quite disappointed with my shader overclock since it seems like a lot of people are getting 1600 or even well above that, but I guess I can't really complain too much because I've also seen people with way less stable cores. Though I can get higher scores benching with the memory at 1332, it artifacts a fair bit. Lowering the memory clock to 1323 eliminated like 99.9% of the artifacting (at least in 3DMark Vantage and 06, and Furmark). It was so difficult to find any problems at that speed that it took me an entire day of testing with it before I was able to definitively spot any sign of instability. Backing off further to 1296 eliminated these problems.

I think hoping for a 740MHz core overclock is setting yourself up to be easily disappointed. That's fairly high, and like I said, every card overclocks differently. The card overclocked at Anandtech for their article supposedly was unstable at anything over 702MHz on the core, for instance.

[Marshmallow64]

I have a EVGA vanilla geforce 275. My card started at the same specs as amtraks at 648/1458/1188. And so far I have got mine to a stable 735/1580/1288 and that's without super trying. I still need to do more tests and stuff to see if I can overclock it higher.

Like amtrak said every card is different and we both got lucky with our cards starting at those specs. It just the luck of the draw. My old geforce 260 could not overclock for squat and it would artifact at the slightest increases so I ended up selling it.

Generally getting better cooling for the case or for the card itself will help overclock it further.

[grishenko45]

thanks both - i'm aware that every card is different - its just that by "good overclocker" to me is a stable 80-100Mhz over stcok on the core.

i was after the xfx gtx275 xxx - which is OC'd to 670mhz on the core - all else @ stock - would you reccomend getting the xfx with stock speeds then OC'ing it myself?

just to make sure its stable - as you said some factory OC'd cards are not stable

[Amtrak]

I think it's a good bet that the vast majority of these cards will be able to clock past that, so I can't see recommending a more expensive card when you could just as easily get there yourself.

[Marshmallow64]

xfx and Evga are good choices, I say if you have a great cooling case and decent room temps you should be able to overclock it no problem. Goodluck!

[Bon3thugz43v3r]

EVGA 896mb 275 here and I max out my core at 730.

[grishenko45]

so the xfx 275 xxx edition @ 670Mhz would still OC past 725 you think???

[Marshmallow64]

I think its really jsut the luck of the draw and it sucks. But chances are the xfx 275 will be able to overclock past 725

[jason4207]

I'm not sure about the 285, but on my 280 the core clock jumps from 729 all the way up to 756. That's a pretty big jump, and you might have to settle for 729.

[Amtrak]

My 275's core clock goes from 729 to 738, then to 756.

[grishenko45]

right then - i'll go for the xfx gtx 275 xx edition which is clocked at 670Mhz with shader and memory @ stock speeds....

it'll be water cooled so when i finish my build - i'll post here the speeds i get out of it