Shader Overclocking

We were able to really crank up the shader core on our GTX 275, hitting almost an 18% increase in clock speed with our 1656MHz shader clock. This is a pretty huge overclock for an already highly clocked aspect of the hardware. While or core clock speed couldn't quite push up like other overclockers, our shader overclock made up for this and was pretty high from what else we've seen out there on stock cooling.

In shader heavy applications, we should see a significant benefit from this, but the reality of the situation is a little bit disappointing.




1680x1050    1920x1200    2560x1600


At best we see about a 7 and three quarter percent improvement in Age of Conan at 2560x1600. This certainly doesn't come near our 18% theoretical maximum. Most of our other tests don't even see the type of performance they got from a much more modest boost in core clock speed. In fact, in a couple cases it makes more sense to overclock the memory than the shader core.

If we take everything separately, the prospects for getting good performance improvement out of the GTX 275 don't look that great. But, even more so than with the 4890, putting overclocking together right can make huge gains in realized performance.

Core Overclocking Bringing it All Together: Everything OC'd
Comments Locked

43 Comments

View All Comments

  • SiliconDoc - Monday, June 22, 2009 - link

    Not only does the gtx275 beat the 4890, but the gtx260 beats the 4870 !
    http://www.techspot.com/review/164-radeon-4890-vs-...">http://www.techspot.com/review/164-radeon-4890-vs-...
    ..
    Oh gee, I guess I should follow dereks chart instead... ( GAG ! )
  • SiliconDoc - Monday, June 8, 2009 - link

    " Given the performance and pricing of Phenom II and the upcoming Radeon 5000 series, if AMD does not pull into black [records a profit] and achieves great sales success, we don't know what needs to happen in order for AMD to actually earn some serious money. "
    LOL
    Will ATI ever make a profit ? We keep hearing how smart they are and how they can really make money while NVidia's monster vore costs nvidia so much ! LOL
    Awwww- poor ati can't make dime one while nvidia keeps posting profits...
    http://www.brightsideofnews.com/news/2009/6/3/ati-...">http://www.brightsideofnews.com/news/20...-has-the...
    ----
    Any red roosters gonna stop crowing about smaller gpu cores and their savings for ATI who loses money every single quarter, anytime soon ?
    Probably NOT - they're so smart, so wise about making gpu's.

  • SiliconDoc - Saturday, June 6, 2009 - link

    Better be careful - from their 4890 extravaganza overclock article they did first and used the results in this comparison against nvidia:
    -
    " We absolutely must caution our readers once again that these are not off-the-shelf retail parts. These are parts sent directly to us from manufacturers and could very likely have a higher overclocking potential than retail parts. "
    YES WE KNOW - NOW YOU'VE TRANSFERRED YOUR RESULTS HERE AGAINST A 703 CORE THAT IS LOWER THAN THE FTW EVGA GTX275 you can but stock faster!
    ---
    You had BETTER look at a few other places that aren't so GD biased it's built in - and Derek is insanely red rooster fan boyed, and hates Nvidia, obviously, like so many little cluckers here for over a year now.-
    ---
    Jeepers- a special 4890 up against non overclocked gtx275 in the 4890 article, then transfer the special results here, and put NOT a regular clocked 4890 as in the other article to be half fair - but jam the massive results in from the special cards they got...
    ---
    I'm mean you really can't screw it up much worse than that.
    They did their best red rooster bias blab possible, I'll say that much for em, and covered it up as best they could.

Log in

Don't have an account? Sign up now