Winner: Intel Core i7-875K
$342; www.intel.com
The Intel Core i7-875K supports Hyper-Threading, Turbo Boost, and 8MB of Smart Cache. And because the Core i7-875K comes with an unlocked multiplier, you can overclock the CPU without adjusting related QPI speeds on the computer. That freedom means you don�t have to worry about making sure that the memory timings, ratios, and voltages are also stable with your overclocks. In some cases, issues with instability in the related interconnects may actually keep you from reaching your peak CPU overclock.
For an Intel processor with a stock clock of 2.93GHz and 8-way processing (four cores with Hyper-Threading), the Core i7-875K is competitively priced. And many enthusiasts have found that the unlocked CPU is capable of reaching 4GHz with an aftermarket CPU cooler, which is a little more than a 35% performance increase. Its ability to reach higher frequencies via overclocking means you get a lot of value for the money. The Core i7-875K also offers instruction set extensions for SSE4.2, which improves visual performance on tasks such as video encoding or image processing.
The Core i7-875K�s 296mm2 die provides room for memory, DMI, and PCI-E (16 lanes that can be run as one x16 lane or two x8 lanes) controllers. For memory, there�s dual-channel support for up to DDR3-1333 memory. We also like that Intel�s Turbo Boost supports speeds up to 3.6GHz, which will come in handy for those who don�t want to push clock speeds too far above the stock 2.93GHz. Intel indicates that the CPU has a 95W max TDP.
First Runner-Up: AMD Phenom II X6 1090T Black Edition
$229; www.amd.com
It�s a comparatively affordable six-core processor, and the Phenom II X6 1090T Black Edition offered AMD�s Turbo Core, which is similar to Intel�s Turbo Boost. With Turbo Core, the Phenom II X6 1090T can automatically boost the frequency on three active CPU cores by up to 400MHz when the processor�s workload allows it. You can also use AMD�s OverDrive utility to manage the Turbo Core settings. In the September 2010 issue of CPU, we were able to push the Phenom II X6 1090T from its 3.2GHz stock clock to 4.1GHz using an Arctic Cooling Freezer 64 Pro cooler.
As you may expect, the Phenom II X6 1090T is AMD�s fastest processor. It features a TDP of 125W and offers 6MB L3 cache. Similar to other Phenom II processors, it supports both DDR2 (up to 1,066MHz) and DDR3 (up to 1,333MHz) memory, though we�ve seen very few Phenom II-compatible motherboards that use DDR2 memory. In our tests, the Phenom II X6 1090T was capable of competing with the majority of Intel quad-core processors, and it was particularly good in multithreaded applications.
Second Runner-Up: Intel Core i7-980X Extreme Edition
$999; www.intel.com
It�s the world�s highest-performance desktop CPU. This 12-way processing powerhouse blew away our benchmark records, but you�ll also be shelling out a little under $1,000 for it, which is why it�s our second runner-up. The Intel Core i7-980X Extreme Edition is based on Intel�s 32nm process technology, which enabled Intel to deliver the faster processing speed, improved functionality, and overall greater computing capability.
There�s 12MB of L3 Smart Cache, an on-chip memory controller for triplechannel DDR3-1066 memory, QPI, Turbo Boost, Hyper-Threading, and support for Intel�s Extreme Memory Profiles. We saw many builders in our Dream PC contest push the Core i7-980X Extreme to 4.2GHz and beyond, so it also has the chops to provide even more processing power. If performance were our only concern, the Intel Core i7-980X Extreme Edition was the cream of the crop.
Source of Information : Computer Power User (CPU) January 2011
