Reaching The Goal
A little more testing revealed 4.9 GHz at 1.60V and new thermal stability limits. Even the slightest increase voltage would cause our CPU to reset at 39° Celsius, and even the slightest increase in speed would lower the temperature at which our CPU reset. We had to get our temperatures down.
Reports from several cooling sites show that the latest compounds can reduce temperatures by up to 4° compared to Zalman’s ZM-STG1, yet our testing showed that a drop of at least 10° would be required to reach full CPU stability at 5 GHz. The logical next step would have been to smooth the evaporator’s mating surface through processes such as precision sanding and lapping, but we weren’t certain how thick this surface was and didn’t want to risk damaging a borrowed product.
We finally reached our 5 GHz goal not by increasing thermal transfer speed, but by reducing heat. Disabling Intel's Hyper-Threading technology dropped us from twelve logical to six physical cores, while simultaneously dropping CPU temperatures by nearly 20°.
The Core-i7 980X has completely unlocked multipliers, yet no multiplier exists to reach 5 GHz at the stock 133 MHz base clock. We also wanted to retain a consistent memory data rate to assure accurate assessment of CPU performance. Increasing our base clock from exactly 133.333 to 166.666 MHz would have been a perfect solution, using a CPU multiplier of 30 and a DRAM multiplier of 4 to reach 5.00 GHz and DDR3-1333. Gigabyte doesn’t use fractional base clock frequencies however, so the actual base clock was increased from 133.0 to 166.0 MHz.
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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