DRAM error

[arges86]

So, my computer is set to turn the display off in 20 min. of inactivity.
I was away from it for a couple of hours and came back. I shook the mouse and nothing happened, there was no signal going to the monitor. I turned the computer off, and tested all the connections. I then restarted it. It just spun the fans, HD, ect. and emitted and error beep that means "DRAM error".
I took out the memory modules (2 of them) and switched their order and replaced them. My computer started just fine.
My question (and i'm sry for the long intro) is what happened? I haven't touched the inside of my PC in months. Is there anything i can do to avoid this occurring again?

My computer is:
AMD: Athlon 64 X2 5200+ 2886 MHz
Mobo: Gigabyte M57SLI-S4 v.2
RAM: 2x2 - 4GB Mushkin DDR2 PC2-6400
OS: Vista 64bit SP2
VC: EVGA 8800 GTS 320MB

 

[sminlal]

If you're lucky it was just a flakey connection with the DIMM socket and it will never happen again...

 

[arges86]

if i'm unlucky?

 

[sminlal]

At this point I don't think I'd dwell on it unless it happens again, unless you're using your PC for something critical that justifies spending the time on tracking down the problem or just replacing pieces on spec.

 

[evongugg]

Test the memory with memtest86+.

 

[arges86]

tested for 8 hrs. w/ no problems