My experience was the same as yours until I learned that EVGA hid a secret killer weapon. Within the bios of the SR-2 (it may be only for CPU's like the 5680's), you can get better performance, with less Vcore and thus less heat. You'll thereby achieve better stability and life maintenance. By underclocking the system (I like 13; 12 sucks) and by relying on its massive turbo boosting potential by raising the BCLK, I can better enforce maintenance of the environmental variables [coolness and low voltage] that allow turbo to trigger. I enable HPET, C1E, all P and T state parameters, hyper threading, turbo boosting and for OSX I use a modified DSDT.aml to enable OSX native power management. The performance benefit shows whether the system is running OSX or Win 7 Ultimate (see, e.g., http://browse.geekbench.ca/geekbench2/chart/show/482744), but it does excel more under OSX (see, e.g., http://browse.geekbench.ca/geekbench2/chart/show/500630 - currently, all of the Mac scores above 31,000, except for the 33,066 score, are mine [at different underclocking values]) because of the way it handles native power management. My favorite 24/7 turbo boost ratio is DDDDEE (13,13,13,13,14,14) with a BCLK of 167. Since the top factory multi is 27 on the 5680's, the turbo is (26x167) or 4.342 GHz for four cores / (27x167) or 4.509 GHz for two cores. Under load while running highly threaded apps it will best most other systems Vcore per Vcore, particularly when running 3d apps such as Cinema 4d. With a Vcore of 1.300 (on CPU0 and 1.275 on CPU1), well within Spec VID, CPU-Z sees its speed as 4.511 GHz (see pics in my earlier posts, above)[under OSX, it's speed is shown as 2.171 Ghz non-turbo and 4.509 GHz turbo]. I have gotten it to achieve a turbo of 4.7 GHz and higher, according to OSX and a mainly steady 4.7+ GHz according to CPU-Z in Win 7, with a 1.35 Vcore on CPU0 and 1.325 Vcore on CPU1 and a BLCK of at least 174. When I run apps that don't trigger turbo boosting like word-processing, browsers and e-mail, my core temps are well below 35 degrees centigrade (now that its fall they hover around 25) and when rendering animations they bounce up to 55-65 degrees centigrade and periodically shoot back down to the mid 30's and immediately back up to 55-65 until the render is complete. I now use Corsair 80's on the CPU's with Sunon fans on a fan controller. Underclocking/biasing turbo yields power (and thus heat) only when the need for power arises. Otherwise, at my favorite setting the system runs extremely cool at idle; and from (13x167) or 2.171 Ghz to (27x167) or 4.509 GHz for single threaded apps. P.S. It'll even save money on the power bill.
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