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Overclocking

Throughout our test session we'll be overclocking the PC. Not because it's so much fun to do but it's because the 680i mainboard series was built especially for it. This is an enthusiast product, it's priced so high as it's special. You have an wide palette of option available to you to torture your mainboard, CPU and memory.

What did we do for the overclock ?

First off, we used a Core 2 Duo E6600 processor on this aircooling.

Memory - now the actual overclock. We have some pretty spiffy Corsair SLI 800 MHz memory to use today with 3-4-3-9 timings. The memory controller on the mainboard uses it's own PLL. So we can clock it asynchronously from the rest of the bus. We set the clock at 800 MHz for the memory with it's best available timings.

Now usually the daunting task of tweaking begins. Often complex and hard to do. For my first choice I decided to not lowest the CPU multiplier yet simple raise the FSB until the mainboard would not boot anymore. Get this... default = 1066 MHz (= a 266.5 MHz FSB).

Remember this formula:

• 4 (Quad pumped Bus)  x 266.5 (FSB) = 1066 MHz
• 1066 : 4 = 266.5 x 9 (multiplier) = 2400 MHz

That is the basis where you can calculate everything from.

1066 MHz - Boots fine (default)
1100 MHz - Boots fine
1200 MHz - Boots fine
1300 MHz - Boots fine
1400 MHz - Boots fine
1500 MHz - Boots fine
1550 MHz - boots fine

So we are now at 1550 MHz : 4 x 9 = 3488 MHz on the processor. Mind you that we are using a simple heatpipe based cooler with a fan. This solution is low noise... and thus not exactly the very best cooler for overclocking.

Let's continue:

1600 MHz - boots fine (3600 MHz CPU)
1650 MHz - boots fine (3712 MHz CPU)
1700 MHz - locks during boot, does POST.

Now what is so interesting here... up-to this point I have not changed anything other then the FSB... the CPU boots up at 3712 MHz without me setting anything else. All setting in the BIOS are still at default; and the mainboard will decide for you if to increase voltages.

So this is really easy overclocking ... I reached 3825 MHz before I ran into real problems. Now I settled the overclock at 3600 MHz. Always build in a safety margin folks, always.

This is one hell of an overclock as the default clock for this CPU is 2400 MHz. That an extra 1200 MHz for performance.

Think of the money you are saving here.. You don't need to but the Extreme Edition X6800 Core 2 Duo processor. You very likely can achieve very similar results with a much cheaper CPU.

A fantastic overclock with really acceptable temperatures... let's do some benchmarks shall we?