I am new to this site but thought I would try for any help and advice for my problem. (Sorry in advance if this post is long-winded but I thought I would try to describe what has happened so far.)
I recently completed my first PC build and it seemed to be all running smoothly until I decided to upgrade further by adding some extra SSD drives to run in RAID0. To do this I chose to do a clean install of Windows 7 64. I had also been experiencing problems with my ATI CrossfireX set-up whereby GPU2 was running at 90 degrees centigrade+ on load (tightening the waterblock screws has seemed to do the trick with load temps now hitting around 45 on Furmark). However, my excitement at now running RAID0 and successfully lowering the GPU temps was soon dampened by sudden shutdowns during gaming. What's strange is the PC would then try to power up, fail, and try again. The first time this happened (about two weeks ago) there was a complete shutdown less than 5 minutes into playing Mass Effect 2, the PC then tried to power up but after one or two seconds died and then, finally, successfully re-booted on the second or third attempt. This evening I was running Furmark Multi GPU on Xtreme Burning mode and it happened again. However, this time it took several attempts before it finally powered up. I don't get a BSOD, just a shutdown and when it finally starts up I get the message asking if I want to start in safe mode etc.
Anyway, this is becoming quite worrying for me, especially because I don't know how much damage these shutdowns and failed start-ups are doing to my expensive SSDs and other hardware. So what do you think could be the problem? Do you think the power supply is faulty, should I get a 1,000+ watt PSU? Could it be the graphics card(s), could the RAID set-up be to blame, or is it something else entirely? What makes it more puzzling is this is all new and, supposedly, reputable hardware:
CPU: Intel Core i7 930 @ 2.8ghz
Mobo: ASUS p6x58de
RAM: 3x2gb XMS3 PC3-12800
GPU: 2 x xfx radeon HD5870s CF
2 x Crucial C300 128gb SSDs in RAID0
1 x Crucial C300 256gb SSD
1x Samsung Spinpoint F3 1Tb
1 x Pioneer BDR 205 BluRay RW
PSU: Corsair HX850
2 x 92mm Gelid Wing fans
6 x 120mm enermax Apollish Vegas fans
2 x UV cathodes
2 x Swiftech MCP655 pumps
I've run Prime95 and MemTest+ to see if the CPU or RAM's faulty but no problems were detected.
Typically if your computer is powering down during heavy gaming the issue is either a heat build up in the case causing the system to power down or under powering from your psu to run all of the needed components at high speed and full power draw. My guess in this case would be an underpowered gpu, especially if you have overclocked the video cards at all. I would start by downloading speed fan or another temperature program and seeing if there is any temp issues popping up (check the manual on your boards for temp tolerances for your gpu's and the chipset/motherboard) than work forward from there. A simple test would be to take out one video card and see if it still happens. If yes, there may be something else going on, if it runs fine, you are probably drawing too much power for the psu.
That's a lot of crap to be running at the same time. Just a quick jump through a wattage calculator, and you're at around 625W, and I'm sure that's not counting several parts and/or overclocking. I'd be willing to bet that you're pushing the PSU beyond what it's capable of. I'd guess that adding the third SSD and actually making all of the cooling work pushed you over the edge.
Why do you think you need 8 fans and two water cooling systems running? I'd remove some of those from the equation. You're running everything at really safe temps, so you could stand to lose some of the cooling to get the machine working. You could also get rid of the completely superficial cathodes. If you unplugged the two 92mm fans, two of the 120mm fans and the cathodes, you'd shed about 30W. That should be more than enough to get you back under the threshold of the PSU. Plan out how you want the air moving through your case properly. With all that gaudy crap you've got, I'm 100% sure you're actually hurting your airflow by introducing too much movement. Really, anything over three (two in the back/top for output, one in the bottom front for input) or four fans (two back/top, two bottom front) isn't doing anything for you.
Or you could turn down some of the overclocking you've more than likely done. Or if you haven't done any, you could just get rid of all that extra cooling, since there's no reason to have that much to run at stock.
Of coures, that's just my guess of what's happening. You could easily test it by unplugging some of the extra crap you don't need and seeing if the problem is fixed. If that fixes the problem, either leave the extra crap unplugged or buy a bigger PSU. I'd suggest leaving stuff unplugged, as it's free...
Forgot to mention that I'm not sure if that 625W load was actually "at load". It's certainly not at 100% load, like it would be when running the benchmarking programs. That 625W also wasn't figuring in any add ons that might be using power (like the keyboard and mouse or external HDDs), or any overclocking. 625W is still closer to the rated wattage than I'd like to be.
Most of the calculators that are out there are ok, but do not take into account full load. Those that do often take into account overclocking the system you are running but do not consider the extra power consumed by overclocking the video card too. It is always something consider when looking at power use.
Put it another way, Newegg's PSU wattage calculator (very primitive, as it only does the CPU type, motherboard type, # of sticks of RAM, # of specific GPUs, # of mechanical HDDs and optical drives) gives a result of 900W. So that range of power usage under typical loads (no overclocking) is likely between 600W and 900W. Running the more intensive programs, which is where the build fails, would push you higher on that range, which would put you out of the PSU's capabilities.
Your guesses were confirmed: insufficient power seems to have been the culprit. Swapping the PSU seems to have done the trick. I managed to get my hands on an Enermax 1250 revolution 85+ to replace the Corsair 850 professional. It has been running a couple of weeks now and I haven't had a single crash.
I have to say having read the good reviews I was surprised the Corsair professional 850watt PSU couldn't sufficiently power my rig , but having said this the ASUS P6x58d-e manual does advise getting a 1000 watt PSU if running a dual GPU set up.
Anyway, I'm very pleased with the new PSU and I like the way the fan continues to run for 20 minutes after shutdown for that extra cooling, although the semi- unsleeved SATA cables were a slight disappointment.
Hope this helps anyone who may be experiencing similar shutdown problems, or is thinking of buying the Enermax 1250 revolution 85+.
Btw, the reason i've got eight fans is I've got four attached to the Black Ice 480 GT Xtreme rad for the CPU (which I plan to overclock as much as possible) and two attached to a 240 rad for the two HD5870 GPUs. There are two 92mm exhaust fans at the back. Is this overkill?