Overclocked Performance

For the purposes of this section we are focusing on the overclockability of the core, but not the memory. NVIDIA’s weaker GDDR5 memory controller coupled with the tendency for memory overclocking to reduce performance through the need to use error detection and retransmission makes memory overclocking much more difficult and often a bust entirely.

As not all of our cards are exactly alike, we’ll quickly run down the differences between the various cards.

  • 1x NVIDIA GTX 460 768MB Reference
  • 1x NVIDIA GTX 460 1GB Reference
  • 2x EVGA GTX 460 768MB SuperClocked: Reference PCB and cooler, factory overclocked
  • 1x Zotac GTX 460 1GB: Reference-derived PCB, custom blower-style cooler
  • 1x Asus ENGTX460 768MB TOP: Custom PCB, custom cooler, factory overclocked, voltage tweak
     
  Stock Clock Max Overclock Stock Voltage Overclocked Voltage
GTX 460 768MB Reference 675MHz 840MHz 0.987v N/A
GTX 460 1GB Reference 675MHz 825MHz 1.025v N/A
EVGA GTX 460 768MB SuperClocked #1 763MHz 850MHz 1.000v N/A
EVGA GTX 460 768MB SuperClocked #2 763MHz 840MHz 0.975v N/A
Zotac GTX 460 1GB 675MHz 835MHz 1.000v N/A
Asus ENGTX460 768MB TOP 700MHz 930MHz 0.975v 1.062v
GTX 460 1GB SLI 675MHz 800MHz N/A N/A
EVGA GTX 460 768MB SuperClocked SLI 763MHz 840MHz N/A N/A

Among our 3 vendor cards without voltage tweaking capabilities, all of the cards are closely clustered together in terms of the final stable overclock, with only a 25MHz difference between the top and bottom cards. The Zotac 1GB card ended up with slightly lower overclocks than the 768MB cards, which is likely a product of the 1GB cards containing further enable ROPs and L2 cache than the 768MB cards. Meanwhile the best overclock on a card we got without a voltage tweak was one of our EVGA cards, which was able to go to 850MHz, while the second EVGA card hit 840MHz, and the Zotac card hit 835MHz.

The lone standout in the group is the Asus card, which has voltage tweaking capabilities that allow us to increase the core voltage beyond the GPU’s VID. In testing we found that anything over 1.062v would ultimately cause the card to fall back to 405MHz, which we believe to be the card’s VRM protection kicking in after the VRMs overheated. At 1.062v we were able to get the card to up 930MHz, a 33% overclock from the factory overclocked speed of 700MHz, and 38% faster than the GTX 460 reference clock of 675MHz.

Overall the impact of overclocking is heavily game dependent. Core overclocking favors games that are ROP/shader limited and has little effectiveness on games that are limited by the total available RAM or by memory bandwidth. For this reason out of our subset of games core overclocking was most effective on Battleforge and Bad Company 2, while only moderately effective on Crysis and STALKER. On Crysis and STALKER overclocking was at best only marginally more useful than having a 1GB card.

The big winner here with respect to performance is the Zotac card, thanks almost exclusively to its 1GB configuration, affording additional RAM/L2/ROPs. Of our 768MB cards the Asus comes ahead most of the time as expected thanks to its greater core overclock, but it does manage to fall to the overclocked EVGA card under Crysis where the latter’s greater stock memory clock clearly offers an advantage.

Currently the sweet spot would look to be a 1GB card with a lesser overclock, which isn’t great news for the overclocking-focused EVGA and Asus cards in this roundup. While they are cheaper than a full 1GB card, they still carry a price over MSRP which cuts in to the gap between 768MB and 1GB cards. Ultimately the additional RAM/L2/ROPs more than makes up for the higher overclocks the 768MB cards can attain in most situations.

Power, Temperature, & Noise Overclocked Power, Temperature, & Noise
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  • VIDYA - Monday, July 12, 2010 - link

    you can overclock them.......you can compute with them.......you can easily scale their performance by just adding another card........and dont have to worry about memory and stuffs. LET ME SAY THIS GPU's have over taken the CPU's in more than many ways.....i would advice intel to develop a better larabee. Reply
  • Lord 666 - Monday, July 12, 2010 - link

    What gives Ryan? You have made your point clear (ad nauseum actually) about the several dollars differentiation between 768 and 1gb along with overclocking, but without a full picture of performance numbers, the review is still lacking.

    Is there still an NDA on the video performance and/or CUDA metrics as I noticed other sites do not have results either?
    Reply
  • Pessimism - Monday, July 12, 2010 - link

    The future you envision is more dependent on NVIDIA deciding to change their business practices and eliminate:

    -Faulty drivers that slip through QA with bad fan control, cooking their products to death
    -Poorly made chips that separate from their packaging with heat under normal operating conditions
    -Lying to their customer base about the existance of problems with their products
    -Refusing to give specific information to customers about exactly which products are defective
    Reply
  • DominionSeraph - Monday, July 12, 2010 - link

    I see ATI marketing is present and accounted for.

    Face it, Nvidia has a compelling product in the GTX 460. If it was priced $30 higher it would be nothing special. If it was 20% slower it would be nothing special. If it was a power hog like the GF100 it would be hard to recommend.
    But it's none of those things. Nvidia managed to sneak a good product in. Their ONLY one.

    Now maybe the 5850 will come back down to launch price ($259), or maybe even $249 which would bring its price/performance in line with the $229 GTX 460.
    Reply
  • mrmojo1 - Tuesday, July 13, 2010 - link

    "-Poorly made chips that separate from their packaging with heat under normal operating conditions"

    I have one of these in my ASUS g1s laptop. I had to have the MB replaced once already due to the nvidia GPU. Looks like it's gonna keep working until my warranty goes out in a month or two... fun stuff =/
    Reply
  • mrmojo1 - Tuesday, July 13, 2010 - link

    oh btw, I like both NVidia and ATI; i'm not an nvidia hater.

    Just a little pissed that a laptop I paid over $2000 for at the time was essentially defective from the start.

    tick tock tick....

    /rant
    Reply
  • irsmurf - Monday, July 12, 2010 - link

    Anyone thinking of going for a GTX 480 would be wise to consider SLI 1GB GTX 460's. 2D surround and better than GTX 480 performance for only $440 - $57.20 CB = $382.80 at TigerDirect.

    It is much more quiet, much more cool, consumes much less power, costs much less, and provides superior performance... what more could you ask for? This is the most kick ass card since the 8800GT. 5970 is TWICE the price... and you don't get SLI's superior scaling.
    Reply
  • irsmurf - Monday, July 12, 2010 - link

    I don't mean to say SLI GTX 460's will outperform the 5970. Reply
  • SantaAna12 - Monday, July 12, 2010 - link

    If the 5850 is the closest comp...then why no 5850CF benches? Reply
  • irsmurf - Monday, July 12, 2010 - link

    $400 vs $620? Doesn't sound like competition to me. Reply

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