I currently own a Dell XPS 420
I have the most recent bios version etc etc.
The system came with 4x1GB DDR2 RAM memory modules,
I recently bought 2x2GB DDR2 RAM memory modules myself.
I've hence pulled out two of the 1gb modules and replaced them with my new 2gb modules hence giving me 6gb RAM, all DDR2.
However I just checked the bios (i think it was the BIOS anyway, i just pressed F2 upon boot to take me to the setup screen) and it shows only 4gb RAM, same goes for what windows shows me.
I'm currently using Home Premium windows 7 64 bit.
Please help me on how to get the the other 2GB of RAM to show up please?
It's possible your ram configuration isn't compatable with the dell board. If the ram is a different speed or two modules are single sided and the other 2 are double sided, then the bios may not like it. You may need all 4 modules to be the same speed, model, and brand. Also be sure the pairs are in the correct slots. Some boards have 1 with 3 and 2 with 4, or slots 1+2 and 3+4.