My Athlon 2800+ cpu (AXDA2800DKV4D) is misidentified on my ASUS A7N8X Deluxe board as an Athlon 2200+. I have the latest bios I could find from ASUS, rev 1009. When I set the cpu frequency to anything above 133 in the bios, the cpu will keep restarting. It will get as far as the Windows XP screen sometimes, like the OS has a problem with the settings once the bios turns things over to it. Some settings don't even get that far. I ran CPU-Z and it also shows the cpu as a 2200+ (maybe it gets its info from the bios?). It also says it has a Barton core and 512 KB L2 cache, so it can't be a 2200+ since they ony came with Thoroughbred or Thornton cores and 256 KB L2 caches. CPU-Z shows the cpu running at 1670 MHz, 12.5 multiplier, 133.6 actual bus speed, with a FSB rating of 267.3 (266) MHz. An Athlon 2800+ should have a 333 MHz FSB rating unless it's a AXDA2800DKV4C (266 FSB) instead of a 4D. Even so, a 4C will run at 2133 MHz with a 133 actual (266 effective) bus and my 4D will only run at 1670 MHz core speed at 133 MHz bus. I should be able to set the cpu bus to 166 or even push 200 for a 2800+ and get a little over 2 GHz core speed. I've tried the agressive bios options, etc, etc, but the only thing that will work is the 133 bus and optimal settings. The core voltage is correct (1.664v). This is a common and old favorite socket A board, and I am hoping somebody has experienced a similar situation and would share their insight.