Hello I'm fairly new to the inner workings of a computer and recently watched a friend rebuild my desktop with a few new parts. I had an 80GB hard drive before, running vista and such but it filled very fast so my friend brought me a 320GB Laptop hard drive and threw it in my PC for some extra space. The first time we booted my machine it recognized it, but since last night when I would boot it only showed the 80. I am concerned I may have bumped a wire or accidentally unplugged something. My friend says it might be because my PSU isn't powerful enough to power everything and it might be prioritizing devices. A little info on my machine, it was an old HP Pavillion a1530e, I bought a new Biostar A770E3 Motherboard, AMD Athlon II X2 245 Processor and a 2GB stick of DDR3 RAM because my old motherboard (we estimated it was around 8-10 years old) had died. We kept the Bestec 300w PSU in it, could this be the issue?