RAM question

i got 1 gig =/ well that sucked but for some reason a while now it keep saying i only have 382 ram i checked and everything i bought this PC with 512 ram and i installed a ram stick it got it up.... and
for like ever now for some reason can i just lose RAM like that for some reason
it now says i have 382mb of ram =/

EDIT : fuck it i gotta get me a new pc D:

Pfft...My computer Has 512MB ram. Its most likly you computer settings. Maby your removing some of its space in your settings. Just guess..

Maybe some of the RAM got a faulty connection. ¬_¬ What I did to fix this was simply take out the RAM and cleaned it with an eraser. It work so XD!!! I dunno try it out or something... Good luck!