Overclocking

Let's talk about overclocking for a second. There are a few factors that affect how a card overclocks, the most important being the type of heat sink on it. Overclocking boosts the performance of the card, but in turn, causes the processor to heat up more. The heat sink is made to expel the heat generated by the card's graphics processing unit, which keeps it running smooth and stable. The risk with overclocking is the possibility of causing damage to the card because of excessive heat. Generally, every card has a "sweet spot" where the clock speed is set high enough to get good performance, yet low enough to ensure that the heat sink will be able to handle the temperature.

Every card overclocks differently, so the data that you see here won't necessarily be the same for every EVGA e-GeForce 7800 GTX. We found our fastest clock speed through trial and error, basically bumping it up more and more until it wouldn't run.

We used Coolbits to detect the optimal settings for overclocking the card and came up with 487MHz for the core clock and 1.27GHz for the memory. We then tested these settings out by looping high- res Battlefield 2 demos over and over for about 45 minutes. Although it ran, there were some graphical tearing and artifacts that showed up on the screen, so we tried a few lower settings and eventually we were able to get it to run cleanly with the clocks set at 475MHz and 1.25ghz. This is as compared to 430/1.2 for a stock 7800 GTX.

After overclocking, we ran some benchmarks to see how well three choice games performed. We'll look at those next.

The Card Performance Tests
Comments Locked

26 Comments

View All Comments

  • masteraleph - Sunday, July 17, 2005 - link

    Where's the comment about Dual-Link DVI on one of the outputs? Shouldn't the fact that this card can run the Apple 30" display be noted somewhere in the review?
  • semo - Saturday, July 16, 2005 - link

    the upcoming 7800 from evga will have (with the green cooler) asymmetric cooling system (acs). xbitlabs has reported on it yesterday i think
  • tommyw - Saturday, July 16, 2005 - link

    I was reading this article http://www.digit-life.com/news.html?119317
    and would be interested to know if Anandtech has any comments on it. According to that, if I understood properly, it is not possible to change the clocks by 1MHz steps, but by 27MHz steps. And that different parts of the core work on different frequencies.

    Interesting how will this change OCing? New challenges, yes :-) !!
  • L3p3rM355i4h - Saturday, July 16, 2005 - link

    Last page type "pricy"
  • Son of a N00b - Saturday, July 16, 2005 - link

    yeah OC'ing is an addiction...I still OC my 6800's a bit to play CSS even though I do not have to everytime I play (i never leave it set to startup for stability issues)....but I cannot play if my cards are not OC'ed

    anyways AWESOME article and idea for it guys! cant wait to see BFG's
  • JustAnAverageGuy - Saturday, July 16, 2005 - link

    Typo, page 3

    7800 GXT

    Typo, page 4

    "PowerStreams"
  • PrinceGaz - Saturday, July 16, 2005 - link

    If I was going to spend about $600 on a gfx card, I think I would enable at least 4x AA in games that work correctly with it. If ncessary drop down to 1600x1200 from the tested 1920x1440 or 2048x1536; my monitor does support 2048x1536 and at a good refresh rate (85hz), but the jaggies are far more noticeable at 2048x1536 without AA, than they are at 1600x1200 with 4x AA.
  • Samus - Saturday, July 16, 2005 - link

    I can't believe they put up all those charts and failed to compare it to ANYTHING other than a 7000 series card. As #2 stated, exactly how many people are going to overclock this card? How many people care?

    I can tell you a lot of people care to know how well it fares against a 6800.
  • Zebo - Saturday, July 16, 2005 - link

    XFX 7800GTX is much better

    470/1250 default OC and a pretty decent game controller included. Some dudes are hitting 490/1300 pretty easy with mild OCing.

    #2 -- I agree for most part.. It's different taking a 1.8 A64 to 2.8, scores will massivly improve..but some of us like to OC everything no matter what..it's an addiction trust me.:P
  • drifter106 - Saturday, July 16, 2005 - link

    #5 thanks for the comment on your card and its overclocking ability...some people just don't know how to comprehend the written word...maybe they need to get their shit together before they make themselves look silly

Log in

Don't have an account? Sign up now