Change the frontside bus setting to 166MHz. It sounds like it is still set at 133. Both your old 1600+ and the Sempron 2500+ use a multiplier of 10.5, so coincidentally if you run the Sempron at 133 FSB, your system interprets it as a 1600+.
okay i just checked at MSI's site on the board info..
i searched for KM2 and found KM2M Combo-L which doenst support CPUs with a bus speeds of 333.. only up to 266.. if thats your board.. then u it can only run at a FSB of 133.. hence u wont be able to run the CPU at its intended speeds. you'll need a new motherboard
JHawk56: Ya know u could have just used the edit button... dont think you're allowed to double post
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