Can anyone help me with this? I have searched tirelessly online to find a solution to no avail. I have an Asus A7V400-MX motherboard with an AMD Athlon XP 2600+ (333fsb) Thouroughbred core and PC2700 ddr ram. According to Asus I should set the dipswitches to be set at 166.67 in order to work. When I do it tells me I have a 1916mhz Sempron. So I played and found when they are set at 133.33 it tells me a have an Athlon XP 2000+. I have tried all sorts of dipswitch configurations, but with no luck. I have come up with it recognizing it as several different processors except the one I have. I did check the CPU and make sure on AMD's website that it was in fact a 2600+ 333fsb and it was. I have also checked and my motherboards BIOS came with the latest BIOS version available. Anyone know of anything else I can do here? Am I missing something? I have built several computers over the years and never had this much trouble... it is driving me nuts!!!