I bought a pc100 256mb stick to addto my 128. I tried to install it into the second DIMM but got an error with the system registry and the computer auto reboots. Took it out and put the 256 into the #1 DIMM and turned it on. Ran fine but only showed 128mb in properties under my computer. Am I missing something here, is there a change to the bios I need to make?