Welcome Stranger to OCC!Login | Register

Intel Core i5 661 Review



The only way to know how a processor performs is to run it through a series of benchmarks, using both synthetic and real tasks to make a comparison as to how the processor performs against architectures from the same manufacturer as well as competing manufacturers. Really, this leaves Intel and AMD at this point. To test the Core i5 661 3.33GHz processor, all of the energy saving features as well as performance boosting technologies have been disabled on the motherboard to be able to gain repeatable results. Otherwise, the results would not be a valid form of comparison. Intel's Turbo Boost technology provides a serious clock increase on this CPU that allow it to deliver performance in excess of what is available when the technology is disabled. A comparison will be made against both AMD processors and both the Intel socket 1366 and socket 1156 processors. Once the stock testing is completed, I will overclock the Core i5 661 to see if it gives up any head room. Both stock and overclocked testing will be accomplished on the Intel DH55TC motherboard.


Testing Setup: Intel Core i5 Clarksdale Socket 1156


Testing Setup: Intel Core i5/i7 Socket 1156

  • Processor(s): Intel Core i5 750 133x20, Intel Core i7 870 133x22 socket 1156 CPU's
  • Motherboard: Intel DP55KG Extreme (Kingsberg)
  • Memory: Kingston HyperX KHX1600C*D3K2/4GX 7-7-7-20 1333MHz
  • Video Card : NVIDIA GTX 260 (216)
  • Power Supply: Mushkin 800w Modular Power Supply
  • Hard Drive: 1 x Seagate 1TB SATA
  • Optical Drive: Lite-On 8x DVD+/-RW
  • OS: Windows Vista Ultimate Edition


Testing Setup AMD AM3 CPU's:


Testing Setup: Intel Core i7 Socket 1366


Comparison CPUs:



Overclocked settings:

  • Processor: Intel Core i5 661 153x25 3.85GHz

After having pretty good luck with the Intel motherboards used on the last two processor launches, I was expecting a little more than what I got. The BIOS options on the Tom Cove board are very limited. Sure, there is a way to bump the bclock speed up, but there are no options to increase voltages or adjust memory timings. Both are serious impediments to overclocking, but when you look at where this motherboard and processor are targeted, there really is not a need to have a BIOS full of overclocking options. Even so, I had to push it to see what could be accomplished with the limited options. The lack of even basic voltage voltage adjustments was the first real problem I ran up against. How so, you ask? Well, with the four sets of memory modules I have, which are rated to run on Core i5 systems, only one would allow the system to run stably at stock settings. Why? All of the modules I have a rated to run at 1.65V. It should not be an issue, but the board set only 1.5V in the BIOS without any possibility to increase it. Again, keep in mind the target for this combo. With the memory problem in check, I disabled the energy saving technologies and started bumping up the bclock in 5MHz increments, with a reboot in between to see if the settings would boot. All was good up to 158Mhz. At this point, I could boot, but blue screen when loading Windows. I backed it down 5 MHz to a bclock of 153 and was stable enough to run Prime95 for 5 hours before bailing on the stability testing. All in all this takes the processor up from an already stout 3.33GHz  to 3.85GHz with nothing more than a bclock increase. It does seem that the graphics core does not see an increase based on the processors bclock speed.




While manually adjusting the BIOS is a way to get your overclock on, Intel has its own way of increasing speed to improve performance with its Turbo Boost Technology. This technology dynamically adjusts the clock speed up to preset limits, in both single and multi-threaded applications - as long as the processor stays within certain parameters that include the current draw of the processor under load. On the Core i5 661 Clarksdale processor, the maximum clock speed you can see using the Turbo Boost Technology is 3.6GHz. In my testing, the maximum I saw was 3.46Ghz in both single and multi-threaded applications. How do you know how fast the processor is running without opening an application like CPUz or Everest? Intel has a handy little tool that comes in the form of a "Gadget" that is used on the Windows Sidebar called, surprisingly enough, the Turbo Boost Technology Monitor. This little tool does exactly what is says it does and will allow you to see just how much extra performance your Core i5 or i7 processor is delivering. Just to see how it worked I ran both the single and multiple CPU tests in Cinebech 10.




  • Scientific & Data:
  1. Apophysis
  2. WinRAR
  3. Office 2007 Excel Number Crunch
  4. POV Ray 3.7
  5. PCMark Vantage Professional
  6. Sandra XII
  7. ScienceMark 2.02
  8. Cinebench 10
  9. HD Tune 2.55
  • Video:
  1. Far Cry 2
  2. Crysis Warhead
  3. BioShock
  4. Call of Duty World At War
  5. Dead Space 
  6. Fallout 3
  7. Left 4 Dead
  8. 3DMark 06 Professional
  9. 3DMark Vantage

  1. Introduction & Closer Look
  2. Closer Look (Continued)
  3. Closer Look: New Control Panel
  4. Specifications & Features
  5. Testing: Setup & Overclocking
  6. Testing: Apophysis, WinRAR
  7. Testing: Office 2007, POV Ray, PCMark Vantage
  8. Testing: SiSoft Sandra
  9. Testing: Sciencemark, Cinebench 10, HDTune
  10. Testing: Additional testing
  11. Testing: Far Cry 2
  12. Testing: Crysis Warhead
  13. Testing: Bioshock
  14. Testing: Call of Duty World at War
  15. Testing: Dead Space
  16. Testing: Fallout 3
  17. Testing: Left 4 Dead
  18. Testing: 3DMark06
  19. Testing: 3DMark Vantage
  20. Conclusion
Related Products
Random Pic
© 2001-2018 Overclockers Club ® Privacy Policy
Elapsed: 0.2122550011   (xlweb1)