Good Day to Everyone,

I have 2, Dimension 9150's that are getting upgrades. The first machine went well with OS WIN 7/ 32 PRO. Bios upgraded (A07), installed software required, no issues, all hardware no issues. RAID driver install also, no issues. Problem I am having is memory upgrade's. Will get machine 2 updated, but not until this issue is resolved.

Been reviewing old post's about memory and still did not find a absolute remedy to my issue. Machine 1 (and 2) are 2 GB; 4 512 PC2-4200 (all slots showing on bios config).  I installed 4; 1GB PC2-5300. Problem ? Should not be as system accepts maximum 4GB and also is at max accepted speed. 

My problem is 2 GB in slot 1-2 (white) are good, no issues (boots to windows no error beeps). Bios check and find that memory sticks are reading correct. When I add the other 2 sticks 3-4 (black), error beeps on boot and showing lights 1-3 lights telling me memory error. 

I recently updated a dimension 4700 and used non dell memory from Komputer Bay. Was able to see all modules and showed 3.76, so I purchased the same memory for this machine. I know in the past Dell machines are "FINICKY" when it comes to memory.

Is this the case ? If so, Crucial memory was discussed and could I just add 2 (2GB each) ? This is what I was not able to see answers for. Some of the post said yes , crucial memory only. The other yes was I could use 2GB sticks. Spec's note 1 GB is max per stick, per slot.

I am at a loss, so looking for some insight on a direction.