Random Power Off

As topic states, My system randomly power's off. No event logs, errors, blue screen, etc.

What I know so far: It happens generally anytime after boot, right after boot, during login process, at the desktop, playing a game, doing work, browsing web, It mostly happens within 10-15 minutes after boot, but it will occur an hour or so after using the computer for general use or during a game, etc...

I'd like some additional opinions/help if anyone cares to aid me in my new found troubles. There is a bit of history to my computer, so bear with this as I describe the actions, issues I had in the past. My current thinking is that my motherboard is having problems, but it could be something else.


System specifications (Self built):
Intel Q6600 Quad Core 2
6Gb DDR2 800(PC6400) (2x2G, 2x1G) RAM
EVGA GeForce GTX 460
OCZ 650Watt Power Supply
Hitachi 500Gb HD
Asus P5K motherboard (Onboard RealTec Audio & network adapter(i think)
ASUS DVD & Lite-on DVD+-RW drives
Currently using a DLink PCI network adapter (part of the story)
Windows 7 Home premium 64bit
(did I miss anything important)


Things I have done:
I run speccy and nVidia monitor, and I'm positive this is not a heat issue, my system has really good air-flow and temps are good:
Idle temps: 22C Graphics, HD: 20C, MB 32C, CPU: 37.
Besides, after being off for a day or so, on boot up, it could be up for about 2 minutes, and shutdown.

I'v tried downloading memtest and run this off USB boot, but I experience shutdowns (no errors indicated thus far, but I have yet to get through a full memory test, it will usually shutdown somewhere in the process, I've seen it as far as about 30% complete, but I don't wait around for it to finish.

Power to room: I haven't done much here, except change outlets and circut, put on UPS, etc.. no effect on issues. Other equipment is not turning off either if on same power outlet or circuit.

History
Network card issues::
After about 3 months (initially having Vista, and about a month after upgrading to Windows 7), my computer started taking a very long time to boot. Rummaging through posts and doing my own diagnostics, I found that after disabling the onboard network controller, the system booted fine. I ended up purchasing a Dlink PCI network adapter and have had success for about 2 years running with this. (meanwhile working with Tech support from ASUS, but not getting anywere, because they would call anywhere from 11:30pm-1:00am my time, I gave up on them, even though it was under warranty).

Some research indicated that an drive update published through Windows updates created some havoc with people that had the p5K motherboard. something do do with Realtech being acquired and new company releasing drivers not tested very well, or similar.

Video Card issue::
About 6 months ago, my computer wouldn't POST, at the time I had an EVGA GeForce 8800GTS video adapter, so after borrowing a friends 9600GT adapter, and testing with that. It would POST fine. Worked with EVGA an issue they agree'd its probably the video card. Unfortunately, I missed the boat on this warranty because It was lifetime and i didn't register this within the timeframe to claim a replacement, otherwise, i they would have shipped me a new one. well, I wanted to upgrade anyway, so I purchased a 460GTX, and the problem was solved. (btw, I didn't get to test my old one on someone else's computer to see if that had issues)

Current Power Issue::
So with the old Motherboard issue, and testing, I have come to the conclusion, that it just might be the motherboard, I'm not sure what else I can test.

Anyone have some other ideas? I'm about to pull a trigger on a new MB, btw with isn't easy with the Socket775, 4 memory slots, ATX form, ...just might have to do some additional upgrades (DDR3 ram...)

thanks all!


----- updates -----
2/10/2012 - I have tested by just going into BIOS and letting it run. It did indeed power off.
2/10/2012 - In process testing Power supply as indicated below

I see in your diagnosing the problem points to a hardware problem with some replacements worked for years. So now you are again in this dilemna and trying to go through the steps of whether the last replaced hardware was the problem or its others. A random power off would be cause most likely by hardware. Did you confirmed the problem by running the system in safemode to check the difference?

I'm assuming since it powers off during memtest86+ which is a simple linux kernel that failsafe mode testing would have the same results. I'll be just putting my comuter into BIOS setup tonight to see if I get the same results.

When a computer begins the boot process the motherboard initiates the start up of the PSU. Because of this it is difficult to determine whether the problem is with the motherboard or the PSU when a computer shows no signs of starting up. The purpose of the procedure is to determine if the problem is with the motherboard or the PSU. For safety purposes please follow the instructions step by step.

This test is for ATX PSUs. Some manufacturers use non-ATX PSUs with 20/24 pin connectors that do not have the same pinout as a ATX PSU.

Caution: This procedure will involve working with live 12VDC electrical potentials which if handled improperly may lead to electrical shock. Proper precautions should also be taken to prevent electrostatic discharges (ESDs) within the case of the computer. For safety purposes please follow the instructions step by step.

First, shutdown your computer. Then unplug the power cable going into your computer.

Once you have opened the case, touch the metal of the case to discharge any static electricity.

The connector of the PSU which connects to the motherboard is readily recognizable by the number of wires in the bundle. To disconnect it you will need to press on the plastic clip to disengage it and then pull the connector up and away from the motherboard. Please take notice of the location of the locking tab and the notch on the socket of the motherboard, this will only connect one way as it is keyed. This wire bundle will have a memory of the way it has been installed and will want to bend back that direction, you may have to play around with it to find a position that the connector will stay in the same position while you run the test.


www.playtool.com

From the top left to right the pins are 13-24, the bottom from left to right are 1-12.


Please notice that there are PSUs with 24 pin and 20 pin connectors, the location of the green wire in the 24 pin connector is #16, and the green wire in the 20 pin connector is #14. If you look at the connector with socket side facing you and the clip on the top the number one pin will be on the bottom left corner. This makes the pin out for the 24 pin connector from left to right 13-24 on top, and 1-12 on the bottom. The pin out for the 20 pin connector from left to right is 11-20 on top , and 1-10 on the bottom. If you look at the connectors you notice that these are sockets that fit over the pins on the motherboard where the PSU cable attaches, this is where you will place the jumper. For a jumper you will need a piece of solid wire about the size of a paper clip (20-22 awg), preferably a wire with insulation. It will need to be large enough to fit firmly into the socket so that it will not need to be held in place while testing. You are at risk of electrical shock if you are holding the jumper when you power up the PSU. Insert one end of the jumper into the socket of the Green wire, and insert the other end into the socket of any Black wire.

Once the jumper is in place plug the cord back in. If the PSU is working properly the case fans, optical drives, hdds, and LEDs should power up and remain on. I would suggest that you not leave this connected any longer than is necessary for safety purposes.

To reconnect the 20/4 pin connector unplug the power cord, remove the jumper, and reconnect the connector. Take a moment at this time to make sure that nothing has been dislodged inside the case.

thanks for the post, I've done this before, but not on the current system. will try asap.

Ok, tested the power supply as indicated above. I believe I'm doing everything correctly, but I couldn't get my PSU to "power-on" jumping the "Power-ON" pin to GRND as you have shown.

My PSU has a 20pin +4pin power connector (i.e. the 4pin is removable), even so, Looking at the pin layout, Green is definitely pin 14 when in 20 pin configuration, or pin 16 if the +4pin is attached.

I tried jumping the green to several black ground pins using a couple different conductors (I had an old PSU at work from a defunct system, so I cut out a piece of the wire, fits perfectly). I also had some copper solid wire around at home and created a small jumper from that. None did the job. At no time did I get the fans to spin up after plugging in the PSU with the pins jumped (no sparks either..lol).

However, I do find it strange, that I can plug it into my MoBo and power it on with the switch. In fact after about 3 boots and power-offs, i am on long enough to write this post.


so, I guess I'm looking at just power supply issue most likely. BTW, I indicated a 650W power supply before, it was actually 600W(i updated original post), I still think i have enough power, I calculated that I need at MAX about 480W to run this system at full power.

sound about right?

Too bad on one front, i was scheming with the wife to pickup a new Mobo with some new DDR3 RAM to fit my rig. I guess I'll have to just settle for a power supply, unless you think I should do some more testing.

if you can't get it to boot using the above test, and combine that with random shutoffs, I would say your PSU is probably toast (loose ground, failing +12v rail, who knows) and replacing it should solve the problem.

Thanks for all the help Patriot_11.

I received my new Corsair HX650W PSU today, installed, and so far, so good.