Question : Problem: Unable to boot with 1 GB RAM modules

First of all, thank you for taking your time to help me. I'm going to try and not limit the possibilities to RAM alone, here are my system specifications.

ASUS Striker Extreme Revision 1504 (Most Recent)
Microsoft Windows Vista Ultimate
Intel Core 2 Quad CPU @ 2.40GHz
2x1GB PC2-6400 DDR2 DIMM 4-4-3-5 2.0-2.1V
Thermaltake 1200W PSU
nVidia GeForce 8800 GTX (Dual Setup)

So, for a couple months, I have been experiencing random system crashes while playing various games (up to then, I was running this setup problem free). It was annoying, but I didn't really see it as enough of a problem to fix since it happened maybe once a day or two. The crashes manifested in BSOD messages most of the time, sometimes it would only crash to my desktop and display a crash report window. The reasons were numerous and seemingly random, display drivers, memory management, page fault, irql, etcetera.

One week ago, I decided I would clean my computer (compressed air blow outs and vacuuming). I was the one who assembled the computer, and I had no confusion reassembling it when I was done. It booted fine and I was playing games again, however the crashes then started to onset much more frequently and predictably. Gradually, my computer started crashing outside of games, to the point where it was a few days ago, it wouldn't even get past POST and then would not even display anything on startup.

I took apart my computer again, this time completely down to the screws which mount the motherboard to the case. Same problem, I couldn't get past POST at best, and often the splash loading screen for the BIOS would be distorted. I never heard any system beeps though, if that tells you anything.

I suspected the RAM first, so I ordered...

1x512MB PC2-4200 DDR2 DIMM 1.8V

because I didn't want to spend too much in case it was (my worst fear) the motherboard. Additionally, I don't know anyone who lives around me who has a computer that supports DDR2, so I couldn't test my RAM in their setup, vice versa.

Surprisingly, the RAM seemed to be the problem. I installed the single module into channel A1 of my motherboard, and for testing purposes I tried A2, B1, and B2. It worked perfectly in A1 and B1, A2 and B2 seating just resulted in the computer not starting up at all. Of course, I was eager to get back to normal, so I ordered some new RAM...

2x1GB PC2-6400 DDR2 DIMM 5-5-5-18 1.8V

I just got them today and stuck them in channels A1 and A2 after clearing my CMOS. Much to my disappointment, I thought I was home free, but as soon as I saw my desktop I received a BSOD with a STOP error. That was discouraging enough, but when I tried rebooting, it wouldn't even show the splash screen, let alone get past POST.

I'm really at a loss for what the problem could be. I took out one of the new sticks to see if maybe that might help, but I receive the same inability to get past POST. I tried all the variations, A1 and A2, B1 and B2, A1 and B1, etcetera. I tried to swap to the 512MB safe stick and that worked just as well as it did before, so it seems like something in my computer is not liking something about the 1GB RAM sticks. I haven't tried experimenting with timings yet, since I am not sure what each a-b-c-d of those timing values corresponds to, but I did try manually setting the voltage. When I set the voltage to 2.2V the 512MB safe stick behaved like the 1GB sticks and wouldn't load the splash screen at all. I've reseated my RAM carefully many times, and clear CMOS before and after every reseat.

Thanks for reading through. If you could give me some ideas that I could try out immediately with the parts I have, I would appreciate it!





In the meanwhile, I'll just address some stuff that someone reading this might ask..

No known power surges or static discharge
I am 99.9% certain of proper seating of RAM at all times, the 0.01% being if the clicks don't indicate they are seated
There is a portable air conditioner blowing into the side of the case at all times
System beeps when no RAM is installed
No uncertainty as to hardware component placement and connections
Playing games is unbearably slow, yet stable

Answer : Problem: Unable to boot with 1 GB RAM modules

I would want to blame the motherboard since the problem cropped up over time and RAM did not fix it.  Is the CPU cooler running (I know - stupid question...)  If the fan is running I would doubt a heat problem, maybe check the CPU temps.  Also, have you tried a single 1GB stick in A2,B1 or B2?  Also, see this, it's not the same as you problem but...

http://www.experts-exchange.com/Hardware/Components/Memory/Q_23013208.html