Hi there, welcome to Tom's.
The speed of your CPU is determined by the FSB (in your case 100) Times the cpu ratio (aka multiplier)
I'm guessing your multiplier is 17..
100Mhz x 17 = 1700Mhz or 1.7Ghz.
Changing the multiplier to 18 would give you 1.8Ghz and so on.
Be careful if you are going to do this though. Keep an eye on temperatures and be aware that if you set your cpu speed to high, your pc will not boot.
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