I have ECS Elitegroup L7VMM2 motherboard, which supports maximum AMD Athlon 2600+ but 266 MHZ FSB max. Ok, I have put AMD 2600+ barton core 2600+ but it is 333 MHZ. I tried resetting CMOS, which didn't work, and when I load into windows it says 1.53 MHZ (which is probably fine since it's not running at 333 MHZ FSB so it's running slower than it's normal 1.9/2.0 GHZ speed) but how do I adjust it to say AMD 2600+. It's killing me having this unknown CPU. lol.