Video performance: Intel Core 2 Quad QX9650 vs Intel Core i5 660.

Lightsmark Benchmark Result i5 660 processor.
Lightsmark Benchmark Result QX9650 processor.

In both of the above benchmarks the following items are identical:

Fedora 12×64

Nvidia Video driver

Evga GTX260 core 216 GPU

4G of RAM

Intel X25-M SSD

The following items are different:

DDR2 RAM for the QX9650 benchmark.

DDR3 RAM for the i5 660 benchmark.

The QX9650 is using an Evga 780i FTW motheroboard.

The i5 660 is using an ASUS P7H55-M Pro motherboard.

The differences in the benchmark results are negligible.   The i5 660 Processor is able to perform within one half of one percent of the QX9650.

Provided the Intel Core 2 Extreme Edition QX9650 processor is an older processor.  But it is a processor that was one of the fastest Intel had ever created 2 years ago when it released.

Advantages:

If you are in the market to buy or build a new computer, the Intel i5 660 makes a very compelling argument for high performance.  Of all things, it is also very energy efficient.   The processor tends to run very cool even under duress.   My testing shows a top temperature of 35 degrees Celsius with stock cooling in a CoolerMaster 690 II advanced case with the stock fans.  If you are using an older processor that is not as powerful as the QX9650 you should see significant performance gain.   Bottom line.  This system has more bang for your proverbial dollar than any other system you can buy or build.   I build and sell i5 660 based systems starting at $1195 plus shipping.  The Intel Core 2 Extreme Edition QX9650 processor cost $1000 on sale typically.

Disadvantages:

The Intel H55 chipset does NOT support dual video cards OR RAID.   If you are interested in those features you will need to step up to an Intel P55 chipset based motherboard to enable them.  The extreme performance crowd will want SLi or Crossfire support that this system can NOT provide.   Even if you use a P55 chipset motherboard you are limited to two video cards running at 8x performance each.  To obtain the full x16  performance on multiple video cards simultaneously  you have to step up to an X58 socket 1366 motherboard and processor.