Trying to install 2 more 4GB DDR2 800MHz 240PIN PC2-6400 DIM on my dell xps 625

mattycrawford

Prominent
Oct 20, 2017
1
0
510
Windows 10 x64
AMD Phenom 9850 Quad-Core Processor 2.50GHz
Bios is updated.
I currently have 2x4gb, wanting to add 2 more, whenever I turn pc on with all 4 inserted i just get a black screen, it works fine with just the 2 new sticks, just the 2 old sticks and also works with 1 new and 1 old together
Any help would be appreciated