How far can I safely overclock a CPU if I’m using a stock cooler? I was building a budget rig and when I had money left over, I decided to upgrade from a high-end Athlon 64 to a really low-end 2.2GHz Phenom. I want to up the performance, even by a tiny bit, but I’m hesitant to do it with a stock cooler. Please help!
There’s no clear-cut way to determine how much performance you’ll be able to squeeze out of your processor. It depends on a number of factors, including your motherboard’s ability to overclock, the reliability of your power supply, and the prowess of your cooler.
The Doctor has found that AMD CPUs tend to be more difficult to overclock than Intel CPUs in terms of how far you can push the processor’s speed. That said, you’re not going to destroy your machine simply because you’re using a stock cooler—not as long as you follow a conservative approach to your overclocking: Start by slowly cranking down your HyperTransport speed and ratching up your CPU frequency.
After each modification, you’ll want to test the stability of your machine. At first, just reset your computer and see if it boots into Windows. As you up the CPU frequency higher and higher, you’ll eventually hit a point where your computer will cease functioning. Note this value, reset your motherboard’s CMOS, and dial the CPU frequency to a few steps below the terminal point. Boot into your operating system and launch Prime95 (www.mersenne.org), our stress-testing application of choice. Run an instance of the app’s torture test for every CPU core you have—if your rig survives, you’ve reached a steady overclock.
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