No, your FSB is defaulted at 100mhz, swithc it back to 133 and that should fix it. Make sure I am right though. I have the same trouble, mine defaulted at 1.2 ghz even though I have an xp 2000+ (1.67). My FSB was at 100, default for 2000+ is suppose to be 133. I changed it back to 133, and it reads as a 1900 on boot up but it's close enough. (Bios has a hard time reading the little processer difference I suppose in socket A's)
As for the RAM your onboard graphics card is using some of it up, it's a shared memory thing. You can't do anything about that.