Help! New computer abruptly shuts off.

I hope someone out there can point me in the right direction. I just
put together a new system and it is shutting off abrubtly for no
apparent reason.

The shutoff occurs during moderate to normal use, but has not yet
happened while idling. Heavy use (gaming, encoding, etc.) does not
increase the frequency of the event. System temps and voltages all seem
well within acceptable ranges seconds before the event. After the
event, the power light remains on, but fans and drives are stopped. I
must switch off or unplug the system, and after about 5 seconds the
power light will turn off. The system will immediately turn on when
power is resupplied.

What I've tried:

* I run the CPU, memory, video, and all other components with the
default settings and latest drivers; I do not overclock.

* OS version is Windows XP Professional SP2 with latest updates.
Antivirus is Grisoft AVG with latest updates.

* System passes all Memtest86+ tests.

2) I have stress tested the system several times using PassMark
BurninTest 4.0 and could not force the shutdown to occur.

3) All zones remain within recommended temperatures.

Any ideas? Thanks much!
--Dave Z.

Below is my system:

* Intel BOXD925XCVLK 925X P4 800 FSB LGA775 DDR2 ATX Motherboard
* Intel Pentium 4 540J Processor Prescott 3.2GHz
* 2 x Kingston HyperX KHX4300D2K2/1G 1GB Kit DDR2 533 Memory
* Antec SX1040BII case with 400 watt power supply
Cooling:
- 1 Intel CPU fan
- 3 Mad Dog 80mm 40CFM 35dB fans (2 rear, 1 front)
- 1 Antec 80mm 2000RPM 17.3CFM 25dB fan (front, cooling drives)
* Mitsumi 1.44 MB 3.5" floppy drive (black)
* 2 x Maxtor DiamondMax 10 6B300S0 300GB SATA 7200RPM Hard Drives
* Sony CRX320EBK DVD 16x + CD-RW 52x24x52 Combo Drive
* Sony DRU500AX Internal DVD+/- RW Drive
* ATI Radeon X800XL Video Card, PCI Express, 256MB DDR
* Creative Labs Sound Blaster Audigy 2 ZS PCI sound card
* APC Back-UPS 650 UPS (w/ serial connection for auto-shutdown)

Just as a followup: Antec recommended that I monitor the power supply
voltage. Fair enough. I performed a stress test (ran Prime95 + PassMark
BurninTest) and didn't see any problems with voltage or temp. I also
couldn't make the system fail while monitoring, so I still don't know
if there is a spike at the time of failure:

High Low
+12C 12.000 12.125
+5V 5.078 5.104
+3.3V 3.332 3.352
CPU Core 1.235 1.306
CPU I/O 1.497 1.497

Proc Zone 55C
System Zone 1 39C
System Zone 2 52C

A short time after the test, when the temperatures had dropped, the
system froze. I'm getting the feeling it's a problem with the
motherboard (bad trace?), but hope someone will have some input before
I try sending parts back. Thanks!

You do not specify the brand of your "400 Watt" power supply unit, but I
have two observations.
1) The number of hardware components in your system probably require MORE
than just 400 Watts to drive when under load.
2) Inexpensive/Off brand power supply units that are rated at "400 Watts"
CANNOT actually consistently deliver anywhere near that amount of power.
Those units are built with inexpensive parts and become unstable in their
voltage outputs when the temperature of the case rises.
Solution: I would recommend getting a NAME BRAND (Antec) power supply unit,
rated at at least 480 REAL Watts.

--
DaveW



"Dave Z." <> wrote in message
news: ups.com...
>I hope someone out there can point me in the right direction. I just
> put together a new system and it is shutting off abrubtly for no
> apparent reason.
>
> The shutoff occurs during moderate to normal use, but has not yet
> happened while idling. Heavy use (gaming, encoding, etc.) does not
> increase the frequency of the event. System temps and voltages all seem
> well within acceptable ranges seconds before the event. After the
> event, the power light remains on, but fans and drives are stopped. I
> must switch off or unplug the system, and after about 5 seconds the
> power light will turn off. The system will immediately turn on when
> power is resupplied.
>
> What I've tried:
>
> * I run the CPU, memory, video, and all other components with the
> default settings and latest drivers; I do not overclock.
>
> * OS version is Windows XP Professional SP2 with latest updates.
> Antivirus is Grisoft AVG with latest updates.
>
> * System passes all Memtest86+ tests.
>
> 2) I have stress tested the system several times using PassMark
> BurninTest 4.0 and could not force the shutdown to occur.
>
> 3) All zones remain within recommended temperatures.
>
> Any ideas? Thanks much!
> --Dave Z.
>
> Below is my system:
>
> * Intel BOXD925XCVLK 925X P4 800 FSB LGA775 DDR2 ATX Motherboard
> * Intel Pentium 4 540J Processor Prescott 3.2GHz
> * 2 x Kingston HyperX KHX4300D2K2/1G 1GB Kit DDR2 533 Memory
> * Antec SX1040BII case with 400 watt power supply
> Cooling:
> - 1 Intel CPU fan
> - 3 Mad Dog 80mm 40CFM 35dB fans (2 rear, 1 front)
> - 1 Antec 80mm 2000RPM 17.3CFM 25dB fan (front, cooling drives)
> * Mitsumi 1.44 MB 3.5" floppy drive (black)
> * 2 x Maxtor DiamondMax 10 6B300S0 300GB SATA 7200RPM Hard Drives
> * Sony CRX320EBK DVD 16x + CD-RW 52x24x52 Combo Drive
> * Sony DRU500AX Internal DVD+/- RW Drive
> * ATI Radeon X800XL Video Card, PCI Express, 256MB DDR
> * Creative Labs Sound Blaster Audigy 2 ZS PCI sound card
> * APC Back-UPS 650 UPS (w/ serial connection for auto-shutdown)
>

Thanks for the reply. The power supply is an Antec SL400. I spoke with
an Intel technician today, and he felt that 400 watts should be
sufficient, but you may be correct. I just finished testing the system
with a different 400 watt power supply (a PowMax) and the system still
failed.

I guess I need to try a higher rated power supplies, and if that fails,
send the motherboard to Intel for replacement.

By the way, the Antec power supply voltages were dead on. The PowGen
readings were somewhat scary, although still within acceptable ranges.

DaveW wrote:
> You do not specify the brand of your "400 Watt" power supply unit,
but I
> have two observations.
> 1) The number of hardware components in your system probably require
MORE
> than just 400 Watts to drive when under load.
> 2) Inexpensive/Off brand power supply units that are rated at "400
Watts"
> CANNOT actually consistently deliver anywhere near that amount of
power.
> Those units are built with inexpensive parts and become unstable in
their
> voltage outputs when the temperature of the case rises.
> Solution: I would recommend getting a NAME BRAND (Antec) power
supply unit,
> rated at at least 480 REAL Watts.
>
> --
> DaveW

"Dave Z." <> wrote in message
> I guess I need to try a higher rated power supplies, and if that fails,
> send the motherboard to Intel for replacement.

I think Dave W has you on the right track.

Dave Z." <> wrote in message
news: ups.com...
>I hope someone out there can point me in the right direction. I just
> put together a new system and it is shutting off abrubtly for no
> apparent reason.
> The shutoff occurs during moderate to normal use, but has not yet
> happened while idling. Heavy use (gaming, encoding, etc.) does not
> increase the frequency of the event.

Not sure how you define "moderate to normal" use, but if you have all
your devices running, I estimate you could be drawing roughly 330
watts or more, not including what the fans are pulling. So it is very
possible you are overtaxing your supply.

Well, you were both right.

Because the new computer is so close in configuration to my previous P4
Northwood system, which runs happily on a 350 watt power supply, I
figured that 400 watts would be sufficient. I picked up an Antec
NeoPower 480 watt power supply and have not been able to reproduce the
problem. Thanks so much for your time.

--Dave

Anonymous Jack wrote:
> Not sure how you define "moderate to normal" use, but if you have all
> your devices running, I estimate you could be drawing roughly 330
> watts or more, not including what the fans are pulling. So it is very
> possible you are overtaxing your supply.