Got an ASUS P5ND motherboard, stuffed into a new case that's about 3 years old. Was running fine for about a week, and then all of a sudden it just shuts down for no apparent reason. CPU temp is good, fans are running. Doesn't matter if Windows 7 is running, or if it's just sitting there after POST. I was moving connectors around, and think I may be loading down a rail. So, I ordered a PC Power and Cooling 750W PSU for it, since I suspect that's the problem. Get to install it tonight, and see what happens. Come on PSU..

start shedding load. disconnect as many items as possible. Take it down to just MB, video and keyboard/mouse. See if it will run.

Did it give you a blue screen with a critical stop error? When I built my rig a few years back, the ASUS mobo gave me lots of problems. Two replacements I had were also DOA. I also have had PSU issues with that computer, but a new PSU along with a replacement one (gave to a friend) solved that. To this day I'm still having issues with it, but it is useable.

How many components do you have? HDs? Vid/phy cards? External components? 750W might not be enough, but disconnecting everything but the bare basics is important too. ALso, run memtest86 to make sure your memory is okay as well (you'll need at least 4 gigs to run Windows 7 well...)

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TC
Current stable:
- 2004 Mazda RALLYWANKEL
- 2007 Saturn sky redline
- 2004 Explorer...under surgery.

Past: 135i, GTI, 300E, 300SD, 300SD, Stealth

Good advice from others so far. One thing I will add - check your mobo capacitors also. I recently had a system that was shutting down on its own....had 4 bad capacitors. The caps should all be flat on top. Bad ones will bulge out and /or leak. plenty of info on the web about this.

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Diesel-guy

Damned mobo capacitors! I've often times had problems with my moFO capacitors . . . Those damned mofos always give me problems!

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" We have nothing to fear but the main stream media itself . . . ."- Adapted from Franklin D Roosevelt for the 21st century

OBK #55

1998 Lincoln Continental - Sold
Max 1984 300TD 285,000 miles - Sold
The Dee8gonator 1987 560SEC 196,000 miles - Sold
Orgasmatron - 2006 CLS500 90,000 miles
2002 C320 Wagon 122,000 miles
2016 AMG GTS 12,000 miles

No BSOD, just a shutdown. It had the mobo, one hard drive, one DVD drive, and a video card. Add two case fans, and that was it. It's got 4 gigs of ram. UPDATE: PSU is in, and running smoothly so far. I"ll let you know tomorrow. It should have plenty of power, it's a one rail design, with a 60 amp rating. Almost forgot to add, power supply is Made in USA. This thing is a beast. Almost 8 pounds, and awesome reviews. It's not cheap though.

Tony, I think a 750 is way too much power. A 603 or 617 should be all you should need. Heck, a 602 would even be enough.
Paul

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84 500 SEL (307,xxx miles)

Your problem is that it is an Intel Machine.

Sounds like the PSU may have been the issue...though the one you just bought is overkill for that PC. I built my brother's PC with that same PSU, and it actually does need it.

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

You should stress test it when you get the new power supply in. I've got a PCP&C silencer 610W running my rig (about 2 years and counting). The 5 year warranty is also quite nice Oh, and 750W is PLENTY. You can run at lot of hardware off of 300W. Check it at the wall if you're curious, or put your hardware in here: http://extreme.outervision.com/psucalculatorlite.jsp

I used to be a fan of a program called Prime95, but, due to simplicity and more capabilities, I like using OCCT now. Here's the link: http://www.ocbase.com/perestroika_en/index.php?Download

Basically, run the stress test for a couple of hours, watch the temperatures (don't let your processor get too hot - maybe 65C max), and check for errors throughout the process. The test will stop if it detects an error. There is also a PSU test that loads up both the processor and graphics card (if it's new enough) to maximize the load on the power supply.

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1982 240D, sold 9/17/2008
1987 300D TurboW124.133 - 603.960, 722.317 - Smoke Silver Metallic / Medium Red (702/177), acquired 8/15/2009
262,715 and counting

Unless running a super high end video card, several hard drives, and a dozen fans.....a 550W Power Supply is plenty for just about any PC. I have a 550 watt with a dual core AMD 7750, two hard drives, two optical drives, 4 gigs of ram, a decent video card, and about 6 fans....and my PC only uses 105 watts at idle....maybe 165 at full load...way below 550!

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-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

Perhaps I have some Tim Allen in me. Hell, it wouldn't work, so I rewired it.. lol The old was a 600W, which I thought would have worked fine. I'm not doing any deep archeticture at the moment, so nothing very taxing. The old PSU was rated for 30 amps, but maybe because it was sitting on a shelf for three years before I used it?? Heck, IDK. I'd rather have more power than I need than not enough.
Crazy Nate, that's what I have, a Silencer Red 750W.
Paul, I wonder if I could get a 616 in there somewhere.
Pawosd, this is all I have running right now. It'll get stuff added. I just wanted to get the machine up and operational for a while before I started stressing it with another video card, hard drive, etc..

Most of it depends on the quality of the psu vs its rated watts. Also, the percent of capacity continuous. The good ones like the PC power and cooling you bought are rated to do full rated output continuously.

My server is running with only a 185 watt power supply....with 0 issues.

__________________
-diesel is not just a fuel, its a way of life-
'15 GLK250 Bluetec 118k - mine - (OC-123,800)
'17 Metris(VITO!) - 37k - wifes (OC-41k)
'09 Sprinter 3500 Winnebago View - 62k (OC - 67k)
'13 ML350 Bluetec - 95k - dad's (OC-98k)
'01 SL500 - 103k(km) - dad's (OC-110,000km)
'16 E400 4matic Sedan - 148k - Brothers (OC-155k)

Well, When I upgraded to a 8800 gts video card, my computer would randomly shut off. So, I took the 420W power supply out, and put in an OCZ 600w power supply. I haven't had that happen since.
I also had no BSOD when it would shut off. It would all die at once. Especially when I was watching a bluray movie...
I would recommend going away from an asus motherboard, and possibly going to EVGA...

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All it takes for evil to prevail is for good men to stand by and do nothing.

Too many people tip toe through life, never attempting or doing anything great, hoping to make it safely to death... Bob Proctor

'95 S320 LWB
'87 300SDL
'04 E500 wagon 4matic

i had a similar problem to yours, no blue screens or anything just shut down it was the memory timing. ive had both intel and amd I like both. AMD gives you more bang for the buck

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1986 300SDL, 211K,Dealership serviced its whole life
1991 190E 2.6(120k)
1983 300D(300k)
1977 300D(211k)

I don't remember the details, but NVIDIA came out with a dual GPU version of their high end video card.
They had to run the GPUs at a lower clock rate.
They figured you'd basically need a dedicated PSU just for the video cards if they ran it full out and you had 2 in a box.

I would bet on the PSU as the issue.
I have a big DB server I run, 11 HDs, nothing else special,well except about 8 fans. It started shutting down randomly with a 500watt PC power and cooling PSU. I put a 750 or 800 watt in and it's been fine since.

Funny though how years ago the HDs would be sucking the power, today it's the CPU and the Video card(s).

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KLK, MCSE

1990 500SL

I was always taught to respect my elders.
I don't have to respect too many people anymore.