Not recognizing any ram in lower slot

I was having some Pram issues last week and got a new Pram battery installed and its working fine, but when I did a system check I was supprised to see I only had 512 ram, I had ordered it with a gig and dont remember if I ever checked it before, anyway I switched the ram around and found both chips seemed to be working, but they were from 2 different makes, I tried 2 1 gigs from a friends computer but always says the bottom slot is empty. the computer seems to run fine & I could opt to buy a 1 gig stick & put in the top but would rather have 2 gigs if possable Any Ideas, I dont think the Pram had anything to do with the problem it seems like I found it by accident

thanks hope everyone has a Safe weekend

you have the common bad lower ram slot issue.... just install a 1GIG module you should be fine.