Random PC Power Off

[timbyng]

I've been having problems with my PC powering off randomly for the past few months. I'll be working away and then *poof*, everything is gone. All I see is a black screen and then it reboots. Sometimes it will happen only once in two weeks and sometimes it will happen twice in a day. I can't figure out a pattern.

I have tried reformatting my computer, but the problem persists. I first thought it was a combination of pcAnywhere and Matrox (since there are known compatibility issues with the two), but the problem still occurred when pcAnywhere wasn’t installed. I have downloaded and installed all of the latest patches/drivers.

Is there anything I can do to figure out what the problem is? It's hard for me to try different things, since it usually only happens once every couple of weeks.

Here are some of my PC specs:
Motherboard: Asus P3V4X
Processor: Pentium III 600 MHz
Memory: 192MB
Video Card: Matrox Millennium G400
Sound Card: SoundBlaster Live!
OS: Windows 2000 Pro SP2

Thanks,
Tim

[Rick]

A couple of thing.
First what size power supply is in the system?
How many other devices are installed in the system (cd-rom, dvd, edit boards)
Is there a common program or action you are performing when the power reset happens?

[Major_Madness]

Welcome to PC Guide!

Let's try eliminating the obvious first and check your electrical connections. Make sure the power cord is seated securely into your PC (does that connection move or is it firm?), then make sure the other end is seated securely into your power strip/surge protector (hopefully you do have one?) then check that its seated properly into the wall outlet. How old is your power strip if you're using one? Have you tried getting power from a different wall outlet?

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I'd rather have a bottle in front of me than a frontal lobotomy

[This message has been edited by Major_Madness (edited 05-21-2002).]

[Paleo Pete]

Random reboots are usually either heat or power supply. Give us more complete system specs, we need to know all components in the machine, (CD ROMs, hard drives etc) and power supply wattage. That will give us better info to go on.

In the meantime, remove the case cover and run it with a small fan blowing inside, and make sure it's not in a room that tends to be warm. If it stops the reboot problem it's overheating. Either the CPU or power supply can over heat. Video cards can overheat too.

That depends on the power supply though, if it's not enough wattage to handle the components installed, it will be overworked, which means it will get hot. We need to know that first, then we can give you a more reliable answer.

While the cover is off, check for built up dust. Especially on the CPU heatsink and fan. That can cause heat problems, since the heat cannot dissipate with a heavy layer of dust on it. If it's dirty, brush it out with a camera brush or make up brush. Make sure it's completely powered down or unplugged. Some people also use cans of compressed air, that works fairly well. Make sure to let it cool completely before using canned air, it could cool it too quick and damage components.

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[UPENDRA UPADHYAY]

I faced this problem On PIII 933, and found Mo/BO power socket Loose, when I replaced it, I Got Rid from random booting. Check Power Socket, it may solve you problem

[timbyng]

Thanks for all the feedback, I really appreciate it!

First, here is a more complete list of my hardware specs. I hope it is sufficient.

Hardware Specs:

Power Supply: ATX-F-250
Fans: 1 Power Supply, 1 CPU, and 1 Chassis.
Motherboard: Asus P3V4X
Processor: Intel Pentium III 600EB MHz
RAM: Kingston 128 MB, IBM 64 MB
Hard Drive: Quantum Fireball Plus AS20.5
Floppy: 3 ½ Inch Floppy Drive (sorry, I didn't check the brand and model)
CD-ROM: Creative CD5233E
Network: D-Link DFE-530TX+ PCI Adapter
Video: Matrox Millennium G400
Audio: Creative SoundBlaster Live! Basic
Keyboard: Microsoft Natural Keyboard Pro
Mouse: Microsoft IntelliMouse Explorer
Monitor: KDS Radius Rad5
Surge Protector: Belkin SurgeMaster


Now for all of the responses (thanks again).


Rick: First what size power supply is in the system?


Here are the numbers off of the power supply:

AC 1/P:VOL:115/230V-CUR:5A MAX:FREQ:50-60Hz
Model: ATX-F-250
+3.3V: 6A
+5V: 12A
+12V: 5A
-5V: 0.5A
-12V: 0.5A
+5VSB: 1A



Rick: How many other devices are installed in the system (cd-rom, dvd, edit boards)


Please see the hardware specs listed above.


Rick: Is there a common program or action you are performing when the power reset happens?


I was using Internet Explorer 6.0 many of the times when it happened. However, there have been times when IE wasn't open and it happened.


Major_Madness: Let's try eliminating the obvious first and check your electrical connections. Make sure the power cord is seated securely into your PC (does that connection move or is it firm?), then make sure the other end is seated securely into your power strip/surge protector (hopefully you do have one?) then check that its seated properly into the wall outlet.


The power cord is securely seated into the PC (it is firm), the other end is seated securely into the surge protector, and the surge protector is seated securely into the wall outlet.


Major_Madness: How old is your power strip if you're using one?


I think it's around 2 years old (maybe a bit less).


Major_Madness: Have you tried getting power from a different wall outlet?


No, but I'm going to be moving to a different address in less than a month, so I'll get to try then.


Paleo Pete: Random reboots are usually either heat or power supply. Give us more complete system specs, we need to know all components in the machine, (CD ROMs, hard drives etc) and power supply wattage. That will give us better info to go on.


Please see the hardware specs listed above.


Paleo Pete: In the meantime, remove the case cover and run it with a small fan blowing inside, and make sure it's not in a room that tends to be warm.


I don't have a small fan at this time, so I won't be able to try this yet.


Paleo Pete: That depends on the power supply though, if it's not enough wattage to handle the components installed, it will be overworked, which means it will get hot.


Please see the previous response to Rick for the power supply specs.

I went into the BIOS and recorded the following information. I'm not sure if this is helpful or not.

BIOS Hardware Monitor Results:

MB Temperature: 28C/82F
CPU Temperature: 52C/125F
JTPWR Temperature: N/A
CPU Fan Speed: 3214RPM
Power Fan Speed: N/A
Chassis Fan Speed: N/A
VCORE Voltage: 1.68V
+3.3V Voltage: 3.50V
+5V Voltage: 4.90V
+12V Voltage: 11.86V
-12V Voltage: -12.08V
-5V Voltage: 4.90V


Note: Even though my computer was on the whole time, the CPU Temperature dropped to 46C/114F about an hour later. The CPU Fan Speed also increased to 3276RPM.


Paleo Pete: While the cover is off, check for built up dust. Especially on the CPU heatsink and fan.


There doesn't seem to be too much dust. I cleaned it a couple of months ago with compressed air (thanks for the tip about letting it cool down first; I'll keep that in mind in the future). I also checked all the connections inside the computer; everything is secure.


UPENDRA UPADHYAY: Check Power Socket, it may solve you problem


The power cord is securely connected to the power socket.

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I hope I managed to answer everyone’s questions; there were quite a few of them!

Thanks again,
Tim

[Rick]

My first suggestion would be to replace the 250 watt power supply.
Install a 300 watt.

If your cpu and case fans are connected to the Mother .
Move them to a power supply / drive connector ...

Your fan speeds are changing .
this is a good sign that your PS and or mother board is not providing a constant voltage/ wattage
A voltage drop during drive access could be causing it.

[timbyng]

Thanks for the reply, Rick.


Rick: My first suggestion would be to replace the 250 watt power supply.
Install a 300 watt.


I will do this next week. Any suggestions on the brand/model of the power supply? I always seem to get stuck with bad ones (usually a problem with the fan, though).


Rick: If your cpu and case fans are connected to the Mother .
Move them to a power supply / drive connector ...


I'm not quite sure how to do this, but I assume that it's not very hard to do. When I replace the power supply I'll make this change. Should I always connect the fans to the power supply?


Rick: Your fan speeds are changing .
this is a good sign that your PS and or mother board is not providing a constant voltage/ wattage
A voltage drop during drive access could be causing it.


Other than doing the two steps above, is there anything else I can do to figure out if the mother board is causing the problem?

Thanks,
Tim

[Rick]

To Move the CPU and Case fans off the mother board.
Follow the fan power cord from the fan to it’s connector.
if it is connected to the Mother board (2 or3 prong plug)

You can get an adapter to connect it to the Power supplies drive power plug ( 4 prong)
if you have a 3 wire plug and wires on the fans and want to keep the tach ( 1 yellow wire) you can get an adapter that will you to do this also.
it connects to the fan power cord and then is split Y with one lead to the M/B for the tach and the other to the power supply drive connector.

Here is an example of a 3 pin to 4 pin with tach
http://www.kdcomputers.com/eui/prime/profile/806/61/component.htm

[ranchdog]

1. Usually isn't a good idea to mix n match RAM. Brand, etc.

2. +3.3V 6A +5V 12A These are extremely marginal.
Need to find a PSU with the strongest +3.3V and +5V legs
possible and affordable. This will prevent random re-boots.


Luck.

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....How long is a minute... depends on which side of the Bathroom door you're on. ......
..........

[timbyng]

ranchdog: 1. Usually isn't a good idea to mix n match RAM. Brand, etc.


Thanks, I didn't know that. I'll try to match it up in the future.


2. +3.3V 6A +5V 12A These are extremely marginal.
Need to find a PSU with the strongest +3.3V and +5V legs
possible and affordable. This will prevent random re-boots.


I have done a bit of research and have found that Enermax and Antec have the most reliable power supplies (is this correct?). I was thinking about getting one with 300+W.

I also downloaded Motherboard Monitor and have saved the High/Low sensor readouts over two hours (recorded every 10 seconds).

Here is the log (I hope it fits):
+-------------------------------------------------------------------------+
|Total number of readouts: 716 CPU Speed: 601 MHz |
|Running from: 05/27/2002 11:43:34 AM till: 05/27/2002 1:42:38 PM |
+-----------------------------+----------+----------+----------+----------+
|Sensor | Current | Low | High | Average |
+-----------------------------+----------+----------+----------+----------+
|Case Sensor | 28° C | 28° C | 28° C | 28° C |
|CPU Sensor | 37° C | 37° C | 50° C | 37° C |
|CPU | 1.70 V | 1.66 V | 1.70 V | 1.68 V |
|+2.5V | 2.50 V | 2.50 V | 2.51 V | 2.50 V |
|+3.3 | 3.50 V | 3.49 V | 3.52 V | 3.50 V |
|+5.00 | 4.92 V | 4.87 V | 4.95 V | 4.93 V |
|+12.00 | 11.80 V | 11.73 V | 11.98 V | 11.80 V |
|-12.00 | -12.03 V | -12.27 V | -12.03 V | -12.04 V |
|-5.00 | -4.84 V | -4.94 V | -4.79 V | -4.84 V |
|CPU Fan | 3245 RPM | 3214 RPM | 3276 RPM | 3239 RPM |
+-----------------------------+----------+----------+----------+----------+

Does anyone see anything suspicious here?

Thanks,
Tim

[timbyng]

I just replace my PSU with an Enermax EG301P-VE. Every time I turn on the computer I get the following message: "Hardware Monitor found an error. Enter power setup menu for details". I checked the Hardware Monitor and it shows my Power Fan Speed in red at 1622RPM. Did I purchase a faulty PSU, or did I do something wrong?

Regards,
Tim

[mjc]

I believe that your Enermax PSU has a fan speed control......either turn up the speed on the fan or disable the monitoring of it.

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mjc
Computer Links (http://www.dreamwater.org/tech/mjc/index.htm)

Celts are the men that heaven made mad, For all their battles are merry and their songs are all sad.

[timbyng]

mjc: I believe that your Enermax PSU has a fan speed control......either turn up the speed on the fan or disable the monitoring of it.


This model does not have the manual fan speed control. Please see the Enermax EG301P-VE (http://www.enermax.com.tw/products/eg-265p-ve.htm) page for more details.

I don't mind disabling the sensor, I just want to make sure that there's no problem with the PSU.

Thanks,
Tim