I was wondering if my RAM could be the problem, I recently installed 3x 1GB and left the 512MB in the 4th slot.
Could it be a problem. Should I purchase a 4th 1GB so that I have 2 pairs of identical Sims, even though my PC will recognize only 3.5 GB?
Thanks for helping out
It would be nice to know what your system specs are and what brand/type of RAM you're using.
At a guess, since you say you have 4 slots, it's probably dual channel. When you run identical RAM in 2 or 4 slots you get proper dual channel RAM, but from what I've read, since you're using 2gb in one channel but 1.5gb in the other, it's actually running as single channel RAM which is going to induce some latency.
Secondly, yes, if that 512mb chip has different specs than the others it can be causing crashes. Could be that it's trying to run at a lower latency than it should, or maybe more voltage than it's meant to handle is causing instability. I definitely think as a first order of business you should get a new 1gb chip identical to your old ones.
After that, run some stability tests. LinX/OCCT/Intel Burn Test are good (Linpack tests). If you can pass 15 runs at the highest "stress" (ie: RAM usage) possible for your system then you're pretty stable. This will stress CPU and RAM. Prime95 lets you stress CPU mostly independantly with their small FFT tests, and Blend tests stresses both CPU and RAM. Anyway, it's good to know you're stable.
The other thing is, do you know what your tempsa re like? Have you cleaned the system out lately? Dust collects after just a few months and drastically affects temps. A little too much dust in the CPU heatsink and you might be experience safety shut downs from over heating, and that will severely impact CPU life. Real Temp is a good monitoring program, or HWMonitor, Core Temp, Speed Fan. Take your pick.