i have a MSI 890GXM-G65 put in 8gb mem 2x4 sticks in bios its showing 8gb but in XP sys its 4gb what am i doing wrong
I think you are using 32 Bit version of XP. A 32 bit OS can access only 2^32 memory location which is equivalent to 3.83 GB. So in a 32 Bit OS you cannot use anything more than 4 GB. For getting the benefit of 8 GB ram, you have to install a 64 Bit version of OS, XP or Vista or Win 7.