Hi all. I recently did a memory upgrade on one of my HP xw8200 workstations. I installed 16 GIG of RAM. When I booted up the computer it instantly recognized the new RAM amount and asked me if I installed the 16 GIG RAM. I hit the yes key and it booted right up and has been working fine ever since. My second 8200 workstation is a different thing entirely. It had 512 MEG of RAM installed in FOUR slots, for a total of 2 GIG. Remember now, it was using FOUR slots. So I pretty much knew those top four slots were working fine. So I bought another 16 GIG from the exact same supplier. Installed it, and when it booted up, it stopped at POST and started beeping in sequences of 5 beeps. I asked here on the forum and it was suggested I start removing sticks of RAM to see if I had a bad stick. I did so and thought I had narrowed it down to one stick of RAM. It booted up fine with 3 sticks at 12 GIG. So I sent the RAM back for an exchange. Today, I got the new RAM module and tried it out...same thing. Stops at POST and beeps 5 times over and over again. Take out one stick and it boots up with 12 GIG just fine. I looked in the Bios but couldn't find anything to change to make it work. So I am asking you guys for any ideas. Can't be a bad motherboard or slots because it recognizes 4 sticks of 512 MEG. No matter what slots I switch to I get the same result. HELP!!!!