Desktop won't boot with 4 GB RAM

[kemperhills]

I am a disabled retired mechanic.  I work on computers to have something to do with my time.

My problem is that the desktop I am now working on won't boot when two sticks of 2 GB ram is installed.  It will boot with two GB in DIMM 1 or DIMM 2 but not when both DIMM's are populated.  

The desktop is a Dell Optiplex 520 that I was given and wouldn't boot.  I found the one stick of ram bad.  The desktop came with XP but I installed W7 Pro x64 to see if the motherboard would run W7.  It had 2 GB bad ram and I replaced the ram with a 2 GB stick.  But I wanted 4 GB ram and I installed another stick and the problem started.  The desktop boots past BIOS and when the Windows icon assenbles as a whole the computer stops booting and will do nothing.  I have to use the power button to turn off the desktop.  

Run 2 GB, well I would but I have a processor ordered and when I get the processor installed I am planning on installing W10 Pro v. 1909 and want 4 GB"s of ram.

Anyone have any idea why the desktop won't boot with 4 GB's RAM.  Thanks.

[kemperhills]

Problem solved.  I was reading some on ram and it said some ram problems could be caused by and older BIOS version.  So I shut down the computer, rebooted, entered BIOIS and found I had an older BIOS version.  Updated to latest BIOS version and now the desktop boots with two 2 GB sticks of ram.  Now I have the 4 GB dual channel ram I wanted when I install the new processor and W120.

[trentenmarschel]

Problem solved.  I was reading some on ram and it said some ram problems could be caused by and older BIOS version.  So I shut down the computer, rebooted, entered BIOIS and found I had an older BIOS version.  Updated to latest BIOS version and now the desktop boots with two 2 GB sticks of ram.  Now I have the 4 GB dual channel ram I wanted when I install the new processor and W120.

Glad to hear you got it fixed. Bios versions, along with motherboard and cpu compatibility, can cause those issues.