Victory At Last?
While our first 5 GHz project helped transform competitive overclocking into a spectator sport, today’s 5 GHz machine achieves some significance for reaching the same speed without the drama that made its predecessors famous. That is to say, today’s project brought a modicum of practicality to the 5 GHz efforts we started six and a half years ago.
Yet, this victory still feels somewhat hollow, and it’s not because dual-core CPUs have already been able to do this for several months. Watching a 5 GHz processor get knocked out by a stock-speed quad-core would have felt like a step backwards. Instead, it’s the remaining impracticalities of pushing a six-core chip to this speed that knocked the wind out of our sails.
First we encountered core temperatures that were too high, in spite of a cooler that never exceeded -40°, and we solved that problem by disabling Intel Hyper-Threading technology rather than addressing the cause. Already feeling that our solution to the heat issue was somewhat lacking, we then noticed that power consumption had increased twice as much as clock speed. Finally, with half the logical cores (on the same number of physical cores) and twice the power consumption, our 50% overclock got us only a 20% average performance gain.
Considering that even our initial 1.35V overclock required a 50% power increase to reach a 25% higher clock speed, it appears that pushing the Core i7-980X by even a moderate amount is wasteful. Those non-overclockers who just breathed a collective “duh” should check out our recent System Builder Marathon, where all three machines increased performance-per-watt by overclocking. Yet, we didn’t try overclocking the Core i7-980X at stock voltage, and we’re certain some builders will find a modest overclock that comes at no cost in efficiency.
Finally there’s the expense. Our $900 cooler requires around 480W of power in addition to that consumed by the rest of the PC. At 12 hours a day of use, that would be 2102 KW/h annually just to run the cooler, worth around $231 at the average U.S. basic residential energy rate. Summer surcharges can double or even triple the cost for anyone whose power consumption exceeds their state’s basic rate limit, a group that includes nearly every electronics enthusiast. Leaving your computer on 24 hours a day to run tasks like Folding@home will double your cost again. If you overclock in an air-conditioned room, the added energy extracted by your air conditioner could double your cost yet again. Thus, while proper system preparation can make phase-change cooling practical in terms of longevity and service life, high cooling cost and moderate performance gains make it a difficult choice to stomach for continuous-duty operation.
Our 5 GHz six-core still makes a great demonstration PC, but the same can be said of any of the liquid nitrogen-cooled systems that have already pushed this same processor model to 6 GHz.
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Pretty impressive. I wish Athlon II would over clock to 4ghz on air. :(Reply
Cooler Master’s reputable CMPSU-850HXReply
Did you mean Corsair?
i thought it would perform much better in gamesReply
tacoslavei thought it would perform much better in games Check this out:Reply
For the CPU to become the choking point, you need the GPU to be extremely powerful. Tom's Hardware formerly used unrealistic tests like Half Life 2 at 640x480 just to prove the CPU performance difference in games, but the fact that nobody used those settings eventually lead to the discontinuation of that testing method.
tacoslavei thought it would perform much better in gamesThere was a thread several months ago comparing the Intel Vs AMD platforms regarding the graphic card bottleneck. Suprising enough Intel cpus capped at a certain overclock where as AMD did not, eventually becoming faster FPS but required a much higher clock speed. It was determined that Intel has a limit on pcie bandwidth. Good luck finidng it, its probably over 6 months old.Reply
back to the arcitle, very interesting, and extremely expensive to even consider doing something like this.
Finally there’s the expense. Our $900 cooler requires around 480W of power in addition to that consumed by the rest of the PCAdd in the cost and time required to set this type of thing up as well as coating the MB ... lol, I don't even want to think about actually trying to go this extreme.
Water is good for me, and if I want extreme, I will wait till winter and throw my radiator out the window while its freezing outside and pump antifreeze through it lol.
zorky9Cooler Master’s reputable CMPSU-850HXDid you mean Corsair?Nope coolmaster has a whole line of PSU's... they are decent and perhaps compareable to Corsair for albeit a slightly lower price point. But Oc'ing to 5.ghz and above is really crazy stuff here. I am actually happy with 3.0 and above already stock but damn, I dont think i would like to tax my system to 5.0 and above, regardless of cooling! It would cost more, but I do see the sport of it and commend those that take time to reach 5.0 and above figures with regular water cooled systems.Reply
Amusing article. However some correcting is needed. The next to last paragraph states the cooler consumed 480W and the cpu consumes according to ur graphic 220w? My math says 700w JUST for the cooler and cpu. This calls in to question ur power bill figures. It's clearly much greater. I won't even talk about once u add things, though it would have been a good idea to calculate that figure too. Simply to show the madness of this project to ur power bill lol!Reply
vinehoyleAmusing article. However some correcting is needed. The next to last paragraph states the cooler consumed 480W and the cpu consumes according to ur graphic 220w? My math says 700w JUST for the cooler and cpu. This calls in to question ur power bill figures. It's clearly much greater. I won't even talk about once u add things, though it would have been a good idea to calculate that figure too. Simply to show the madness of this project to ur power bill lol!The article specifically states that the "added expense" figures are based on the 480W it takes to run the cooler. It assumes you're already planning to use the rest of the system at whatever speed you can get WITHOUT the cooler, and tells you how much MORE it costs to use the cooler. I think its fairly well explained, but feel free to point out any specific spot I missed, thanks!Reply
liquidsnake718Nope coolmaster has a whole line of PSU's... He's right, CMPSU-850HX is a Cosair model. Cooler Master does have some decent 850W power supplies though, I have one sitting in my liquid cooling bench station.
id like to see them try it on the phenom II x6Reply
I'm sorry but once again, Tom's is testing CPU's while bottlenecking the Video. Can't you guys just use a simple rule like: When you test the CPU, use highest available video power (like Xfire of 5970), and when testing the GPU, use highest available CPU (980X). It's THAT simple. The 3D benchmarks are meaningless, waste of time AND money AND information. I predicted those graphs in the moment I saw you used a 5850 for the tests.Reply