I'm really sorry if there are other threads like this already, I lightly glanced at the front page of motherboard/memory threads to see if there were any and didn't see anything so I'm just going to start my own.

I recently got a combo package (cpu, motherboard, ram) from TigerDirect. Intel Q6600, XFX 680i motherboard, 4GB of OCZ DDR2 RAM. I don't think I've gotten a "normal" shut down on my computer yet. Every single time it shuts down is because it froze over night or when I was watching a movie or playing a game. It will be running everything fine and then suddenly go to black and continue sound for a couple seconds and then just stop everything and turn off. No weird sounds, no warning. My CPU doesn't even need to be doing anything intensive. It just froze right now when I was typing this when firefox was my only open window. I downloaded and burned a copy of the ultimate boot cd and did some diagnostics for hours and hours and nothing showed anything. I did Memtest x86+ 1.7 (i think thats the version) twice. Both sessions were about 5 and a half hours and no errors were found.

Here are my system specs
500W PSU Antec SmartPower (I got it in 2005--Maybe it's old?)
Intel Q6600 2.4ghz
XFX 680i LT
4GB PC6400 DDR2
GeForce 8800GT
Windows Vista x64 Ultimate

I just got these new parts and they are becoming more and more unstable. The temperatures are always within normal areas and I haven't overclocked anything. Also, I'm not sure if this is important, but about a week ago my computer suddenly was without a bootloader...so I tried some stuff and when it didn't work I had to re-install vista. Since then, the nVidia control panel app won't install or work correctly.

Ok, I've tried to provide as much relevant information I could. Any help would be greatly appreciated.

Power supply, it appears to short circuit from overload.
Especially since you say it just shuts down.
We've had soo many broken antec you wouldn't believe, they're worse than stuff that comes bundled with cases, and some work perfectly fine at near max load.. Very uneven quality crew there..

I have had very good success with Antec PSU's. OTOH, I agree with asdasd.

I'd change PSU's, first.

The failure mechanism is probably something like this:
Something inside - probably the 12 volt rail - intermittently craps out because of overload, temperature, sunspots, phase of the moon, whatever. Control circuits inside the PSU force a CPU reset and electronically shutdown the PSU.

You may want to try something like XP 32-bit to see if it's a driver issue.

I'm not sold on it being a PSU issue, though it could be.
You could try increasing your memory voltage ever so slightly or loosening your timings.

I would try zens suggestion...btw, what are your voltages...cpu,ram,gpu,etc.

wow, first of all thank you all for the replies. I really appreciate it.

I'm hesitant to say it's the PSU because my old set up NEVER crashed. I had an Athlon X2 4200+ (that's the dual core, right?) and 2GB of RAM before. I'm just confused because I have so many variables. My motherboard, proc, ram, and OS all changed. The only thing that stayed the same out of my whole system (I even bought a new case!) is my power supply.

Anyway, here's the voltages. (I'm just going to list off everything in the nVidia Monitor)
CPU: 1.3125V
Memory: 1.8V
FSB: 1.2V
HT(SPP-MCP): 1.2V (I don't know what that is)
PCI-E: 1.25V
nForce: 1.5V
AUX: 1.5V

Everything should be the stock setting.

CPU-Z says different things because my system runs slower when its not under load therefore doesn't use as much power. If you guys are right about the power supply being bad then that explains why my computer crashes every single time I run Sins of a Solar Empire (I haven't gotten to the menu yet) but not why it crashes while writing forum posts. Also, I'm not sure how or what to change my memory timings to. I know that memory timings are what people refer to when you say 4-4-4-4 numbers hyphenated but I don't know how to change it. I was really into computers a while ago and I liked programming in high school so I will be able to understand things you guys explain but I don't know very much because I don't read any computer magazines or keep up with websites anymore.

If you're running decent ram then bump your ram voltage up to 2.1 volts and do a reboot..
Most high end or decent ram uses 2.1volt.
as far as timings go you'll have to give us the type of ram you are using and the specs for that ram......

i just changed the ram to 1.9 and I haven't had any crashes yet. that might have been it. what a simple solution. I didn't want to put it all the way to 2.1 because that seemed like a pretty big increase and I've heard that over volting is really the only way to damage stuff when overclocking. I realize we weren't overclocking just then but still, .3 volts more is a 16% increase. Seems like a lot to me. if you're sure nothign bad could possibly happen I'll change it. if it won't do any damage could you list scenarios that would be over volting? like if your proc is a 1.3 and it goes to 2.0 that seems like over volting.

ok nevermind, it still crashes, i was just getting lucky. nothing has changed except for the voltage of my ram up to 2.1v

maybe I was misleading with my initial post. my computer doesn't turn off, it just goes black and sometimes will reboot itself. i will be doing a normal task and the screen might flicker once or twice but pretty immediately will just turn black and be dead. the power supply keeps running. all fans keep running. nothing changes at all except for my screen going black and the computer just stops doing everything.

^ That looks like a GPU or motherboard problem or PSU. Btw, if that was the RAM you got (CPU Z screen) you might have been ripped off. Your OP says it is 4GB PC6400 DDR2. The screen shot shows it as PC5300.

Some mobos underclock your ram until you get into bios and set it correctly yourself. I would try kicking the ram up to the required voltage, your not going to void your warranty doing so. Also pull out your sticks, put them in one at a time, and see if one seems to cause failures, i know it sucks, but memtest only goes so far, i had 4 gigs, pulled out both sticks, threw them in one at a time, and found one to be faulty, but when i ran memtest it said they both passed on multiple testing runs. Sometimes the hard way is the only way.

ok now I'm really confused about my RAM. I went to the OCZ website to see if it said anything about that particular product line and it said

"In order to boot on some motherboards this product is programmed to 667MHz; to run at 800MHz you will need to manually set the speed to 800MHz and voltage to 1.8V in your BIOS."

Well, I went into my bios and changed it from 667MHz to 800MHz...my system booted up...everything seems fine...but CPU-Z is the same. It still says Max Bandwidth PC2-5300 (333MHz).

IMO you should see under memory tab instead of SPD tab (with CPU-Z). The SPD tab will show your memory factory specifications instead of actual speeds

And one more issue: are you 100% that your OCS memory is PC2-6400? I got confused here. See your bill of quantity or receipt or mem box or anything to see the spec ..

For your shutdown and instability issue, I would say I agree with shadow ... After shadow post, normally nothing I can add. He always has good post/input

Have you tried a fresh install of windoze?
If not, use only 2 gigs for the install and system drivers, etc.
After it's up and fully updated do a few shut downs to make sure it's working fine.
Then add the next 2 gigs and maybe run memtest just to make sure there are no mem issues.

antas -

I typed in the "part number" given from CPU-Z into the OCZ website and it came up as PC2-6400. it just says that it is defaulted to 667 for some reason instead of 800.



does that mean it is functioning at the correct speed?

johnny -
yes when i got all my parts i reformatted and went from xp64 to vista 64. recently my bootloader got deleted some how (I really don't understand, I'm not an idiot, i don't click on random links, i don't download anything, i dont delete random folders.) so i had to reinstall vista about a week ago and since then it has been crashing more and more. since i've changed my memory settings to 800mhz and 2.1v it has been running a lot more steadily but we will see. this has happened before and it just ends up me being lucky and it not crashing.