Power, Temperature, & Noise

As we’ve discussed in previous articles, with the Fermi family GPUs no longer are binned for operation at a single voltage, rather they’re assigned whatever level of voltage is required for them to operate at the desired clockspeeds. As a result any two otherwise identical cards can have a different core voltage, which muddies the situation some. All of our GTX 460 cards have an idle voltage of 0.875v, while their load voltage is listed as below.

GeForce GTX 460 Load Voltage
Ref 768MB Ref 1GB EVGA 768MB #1 EVGA 768MB #2 Asus 768MB Zotac 1GB
0.987v
1.025v
0.987v
1.000v
0.987v
1.000v

Our cards end up ranging from 0.975v to 1.025v, a variance of 0.05v. The 1GB cards with additional functional units on average require more voltage to operate, with the lowest of our samples requiring 1.0v. Otherwise 3 of our 4 768MB cards require 0.975v.

We’ll start with idle temperatures. With an unofficial idle TDP in the 20W range, the GTX 460 series is fairly comparable to the Radeon 5850, but with a more breezy reference cooler. As a consequence we can see all of our GTX 460s edge out the rest of our cards here, with the EVGA and Asus cards coming in at 34C idle, while the blower-based Zotac card comes in a hair warmer at 35C. Even with a blower, these end up being the coolest mid-range or better cards we have ever tested, besting even the Radeon 5850.

As for load temperatures, we have a mixed bag depending on which card we're looking at. The reference-based EVGA cards do only slightly worse than 60C in Crysis, while Asus’s non-reference card gets that even lower thanks to a more aggressive fan. Zotac’s blower doesn’t fare so well here though, coming in at a still respectable but nevertheless higher 73C.

Our idle power numbers continue to lower the bar for GPUs of this performance class, although at this point we’re hitting the efficiency limits of our PSU at low wattages. Our 768MB GTX 460s end up sharing the 160W mark with the Radeon HD 5750, while for 1W more you have the Zotac 1GB card.

Meanwhile when looking at load power consumption, we see the cards seperate some due to their differences in memory capacity and factory overclocks.  The Asus card with its smallest overclock draws the least power under Crysis at 278W, while the EVGA card with its greater overclock comes in at 284W, and the 1GB Zotac follows at 289W. Under Furmark the same order is maintained, at 314W, 319W, and 325W respectively.

Finally we have our look at noise. With cool running cards we often have to look at fan noise to ensure that they aren’t accomplishing that trick by sounding like a jet engine, with some interesting results to see. At idle both the EVGA and Asus cards are hugging the 42dB sound floor in our testing environment, with the Asus card coming in slightly louder by 2.3dB. Meanwhile the Zotac GTX 460 is at entirely the wrong end of our charts. Blowers can be quiet, but the Zotac’s is not – at 51.4dB it’s simply a loud card. Unfortunately this kind of an idle noise level is going to put the card out of the running for a lot of buyers.

Load noise is more or less like our idle noise results. The reference-based EVGA card comes in the quietest at 46.9dB, while Asus’s card cracks 51dB as its tuned for cooling over noise. Unfortunately the Zotac card is once again the odd man out at 61dB, roughly as loud as our reference GTX 470 is. It’s neither cooler than our reference cards nor quieter, which doesn’t bode well for this stock-clocked card.

The Test Overclocked Performance
POST A COMMENT

31 Comments

View All Comments

  • ClownPuncher - Monday, July 12, 2010 - link

    $460 vs $580 you mean! Though, for a 2 card setup, I would say getting a pair of gtx460 is a no brainer at this point. Reply
  • tviceman - Monday, July 12, 2010 - link

    Both AMD and Nvidia have released several updated drivers with performance improvements since the gtx400 series came out. It would be nice if you guys could do a benchmark review of Nvidia's 400 series cards vs. AMD's 5000 series all using the latest drivers so all your readers (including me) can get a clear picture of how each card stands with the most updated drivers. Reply
  • tviceman - Monday, July 12, 2010 - link

    It would be a great, informative article - a very informative article focusing on performance and high end parts with as updated as possible drivers and a quick overview of current prices. Reply
  • Etern205 - Monday, July 12, 2010 - link

    One possible reason why Zotac's attempt at HD5850's cooling at failed is the HD5850 isn't reference cooling doesn't really blow hot air out of the case. If you take a look at a reference card, there will be 2 slit vents located at the top of the card, which also lets hot air out and back into the case.

    Here is a picture of it
    http://yfrog.com/j8hd5850dj
    Reply
  • Etern205 - Monday, July 12, 2010 - link

    Sorry, link is not working...
    Correct link

    http://img692.imageshack.us/img692/516/hd5850d.jpg
    Reply
  • setzer - Monday, July 12, 2010 - link

    One question, why still use the 10.3a drivers? Even if you say performance hasn't changed (part 1), it's only fit to compare latest drivers to latest drivers. Reply
  • d4a2n0k - Monday, July 12, 2010 - link

    Because they just use the numbers from previous benchmarks and those were the drivers used at that time. Reply
  • Ryan Smith - Monday, July 12, 2010 - link

    Basically this. I do spot checking on new drivers to find performance differences, but I don't run every last test on every last card on every driver (a full NV+AMD rebench is over a weeks' labor). For that reason 10.3a is listed since that's the driver version those numbers came from. Listing 10.6 would be dishonest even if the numbers are the same as we haven't tested every single configuration with 10.6. Reply
  • tviceman - Monday, July 12, 2010 - link

    Which is why it would be great to get a re-evaluation of both AMD's 5800 series and Nvidia's 40 series all with the latest drivers. Both camps have released come out with several driver revisions stating mild to moderate performance gains in many of today's games. It would give an excellent indication as to how far both camps have come along since they released their cards, and most important it would give a more clear indication as to how performance is right now, as opposed to recycling months old benchmarks. Reply
  • Ryan Smith - Tuesday, July 13, 2010 - link

    The numbers from the 10.3a drivers are still accurate for the 10.6 drivers. Or in other words, the performance "right now" is the same. Reply

Log in

Don't have an account? Sign up now