Cant launch xp after installing an ekstra ram

[zniff]

i installed xp on a computer with 2gb ram
and after that i stabbed in another 2gb ram the computer wont start xp
it either goes bluescreen for a few seconds or just restarts after loading

i guess its something i must fix in the bios considering im certain i

power supply 480w
motherboard: p5b-vm
cpu: 2.8 intel dual core socket 755
harddisk: western digital 320gb
ram: corsair 800mhz 2048mb
5-5-5-18 xms2-6400
dvdrom:some random thing from a 4yr old pc

 

[saint19]

Install only the new RAM stick and try to turn on the rig.

 

[zniff]

seems like the it does not work at all
and i put back the other one and now that one doesnt work either

 

[saint19]

Reset the BIOS install the old one and RMA the new for change.

 

[zniff]

hm the ram sems to be working fine when i reinstall xp 64

 

[zniff]

this is ridicules i format install xp with 2gb ram and the finish install and turn off pc and input second piece of ram now it works fine only that i have 2.75 gb ram
nothing is wrong with the piece of ram some sort of setting i have to mess with