A while ago, I bought a 1GB stick and installed it into my PC. It's still working fine now, but now I'm about to install Windows 7 Home Premium 32-Bit and I don't have enough RAM to run it on. Because someone close to me insisted that I can have both a 512MB RAM and a 1GB RAM together installed into my PC (2006/2007-ish Compaq Presario SR2163wm), I did that and now I have both cards installed together into my PC as I type this. I should note that right now it only seems to detect the 1GB card. EDIT: Also, my PC doesn't detect the 1GB card as, well... "1GB". It's actually 894MB. My main question is: If I combine two different RAM cards into my PC, will it add them together? Or do I not know what the bloody hell I'm talking about and I'm just about to ruin my PC?