Fans surging

[jinxy]

Hello, I have an old Compaq Presario S5200nx. It has a Celereon
running @2.6, a p4g 533-la mobo, 512ddr pc 2700 ram. The os is XP
home.Yesterday I could not get it to boot. When I turned on the power
both the cpu and the power supply fans would start surging ,speed up
and then slow down, over and over. I changed the psu, but still
surging fans.
Anyone have an idea as to what is causing this? TIA
-J

 

[GlowingBlueMist]

Hello, I have an old Compaq Presario S5200nx. It has a Celereon
running @2.6, a p4g 533-la mobo, 512ddr pc 2700 ram. The os is XP
home.Yesterday I could not get it to boot. When I turned on the power
both the cpu and the power supply fans would start surging ,speed up
and then slow down, over and over. I changed the psu, but still
surging fans.
Anyone have an idea as to what is causing this? TIA
-J

Time to plug the computer into another outlet, preferably one on a different
circuit breaker. If that fixes the fan issue then it is time to get an
electrician in to see what is wrong with the original outlet.

Try another power cord to the power supply if you have one, they can go bad
too.

Other that I would unplug the power connectors to everything but the
motherboard and the fans and see if the problem still occurs. If it does
then it's time power back down and pull out any circuit cards and see what
the fans do. Again if the problem is still there then it sounds like a
motherboard issue. If the fans were stable with only the motherboard hooked
up then power down and plug something back in and power on, etc until the
problem device is found.

 

[jinxy]

Time to plug the computer into another outlet, preferably one on a different
circuit breaker.  If that fixes the fan issue then it is time to get an
electrician in to see what is wrong with the original outlet.

Try another power cord to the power supply if you have one, they can go bad
too.

Other that I would unplug the power connectors to everything but the
motherboard and the fans and see if the problem still occurs.  If it does
then it's time power back down and pull out any circuit cards and see what
the fans do.  Again if the problem is still there then it sounds like a
motherboard issue.  If the fans were stable with only the motherboard hooked
up then power down and plug something back in and power on, etc until the
problem device is found.

I have also Googled this problem. Some of the readings say it could be
a bad thermal sensor on the mobo.Will try the take apart method
tonight and see what happens. I will post back if I find the answer.
-J

 

[Paul]

I have also Googled this problem. Some of the readings say it could be
a bad thermal sensor on the mobo.Will try the take apart method
tonight and see what happens. I will post back if I find the answer.
-J

I'm guessing the fan symptoms, are from the CPU failing to POST
and run BIOS code.

Check for bulging or leaking capacitors near the CPU socket. I
can see at least nine caps, that I'd want to visually inspect.

http://121.33.239.180/sell/pic/temp/asus-p4g533-la-front.jpg

The second cap from the left in the following picture, is pretty "ripe" and
will leak soon. The rightmost cap, is having its rubber seal on the
bottom of the cap, blown out, causing the cap to tilt at an angle.
When they leak, you may see a brown or rust colored deposit on the
capacitor. At one time, you could get a motherboard "recapped" for
$50, but I expect the people doing that, would be starving to death.
(They'd need to charge more, to pay the bills.)

http://www.badcaps.net/images/caps/ka7/ka7_0149.jpg

Modern systems, have PSU fan speed controlled entirely by the PSU.
But on a limited number of older systems, I understand they
had the idea, of controlling the PSU fan from the motherboard.
So a dead motherboard, could make funny symptoms for the PSU fan.
I don't have any proof to offer though. I'm not going to recommend,
for example, that you remove any three wire cables, running from
the PSU, to the motherboard The PSU could possibly overheat, unless
the PSU is designed to run the fan at full speed, when the cable is
missing.

Paul

 

[jinxy]

I'm guessing the fan symptoms, are from the CPU failing to POST
and run BIOS code.

Check for bulging or leaking capacitors near the CPU socket. I
can see at least nine caps, that I'd want to visually inspect.

http://121.33.239.180/sell/pic/temp/asus-p4g533-la-front.jpg

The second cap from the left in the following picture, is pretty "ripe" and
will leak soon. The rightmost cap, is having its rubber seal on the
bottom of the cap, blown out, causing the cap to tilt at an angle.
When they leak, you may see a brown or rust colored deposit on the
capacitor. At one time, you could get a motherboard "recapped" for
$50, but I expect the people doing that, would be starving to death.
(They'd need to charge more, to pay the bills.)

http://www.badcaps.net/images/caps/ka7/ka7_0149.jpg

Modern systems, have PSU fan speed controlled entirely by the PSU.
But on a limited number of older systems, I understand they
had the idea, of controlling the PSU fan from the motherboard.
So a dead motherboard, could make funny symptoms for the PSU fan.
I don't have any proof to offer though. I'm not going to recommend,
for example, that you remove any three wire cables, running from
the PSU, to the motherboard The PSU could possibly overheat, unless
the PSU is designed to run the fan at full speed, when the cable is
missing.

    Paul- Hide quoted text -

- Show quoted text -

Does this make any sense? I pulled out the 512, 333mhz CL2.5 and
replaced it with 2x 256 400mhz CL3 and away she goes. The system
posted and windows loaded and running fine. Next I will blow out the
tower and reseat the original ram module and see if it posts, if not
then I am guessing the ram is toast. If it posts then I will let it
run overnight to see if it is going to shutdown,maybe a heat thing?
Your insights are always welcome. Thank you for your time and efforts.
-J

 

[Paul]

Does this make any sense? I pulled out the 512, 333mhz CL2.5 and
replaced it with 2x 256 400mhz CL3 and away she goes. The system
posted and windows loaded and running fine. Next I will blow out the
tower and reseat the original ram module and see if it posts, if not
then I am guessing the ram is toast. If it posts then I will let it
run overnight to see if it is going to shutdown,maybe a heat thing?
Your insights are always welcome. Thank you for your time and efforts.
-J

So the RAM must have been bad, down in the area reserved for BIOS usage.
That would be low memory. By placing new RAM in it, you made room for the
BIOS. In some cases, the BIOS seems unable to beep a "bad RAM" code, when
the RAM is bad in low memory. I had that happen on an NForce2 board - a
silent failure with black screen, caused by bad RAM. By moving RAM sticks
around, I was actually able to make that system POST, while the bad
stick of RAM was present. As long as the bad RAM, appears higher in the
address space, then the BIOS runs, and you can even boot. You can boot
memtest86+, and then see what kind of problem exists. In my case,
an entire RAM chip failed, and no matter what location was tested,
returned garbage. (The errors scroll off the screen.)

Some good diagnostic work on your part. I didn't think to suggest that
(bad RAM in BIOS area).

Paul

 

[jinxy]

So the RAM must have been bad, down in the area reserved for BIOS usage.
That would be low memory. By placing new RAM in it, you made room for the
BIOS. In some cases, the BIOS seems unable to beep a "bad RAM" code, when
the RAM is bad in low memory. I had that happen on an NForce2 board - a
silent failure with black screen, caused by bad RAM. By moving RAM sticks
around, I was actually able to make that system POST, while the bad
stick of RAM was present. As long as the bad RAM, appears higher in the
address space, then the BIOS runs, and you can even boot. You can boot
memtest86+, and then see what kind of problem exists. In my case,
an entire RAM chip failed, and no matter what location was tested,
returned garbage. (The errors scroll off the screen.)

Some good diagnostic work on your part. I didn't think to suggest that
(bad RAM in BIOS area).

    Paul- Hide quoted text -

- Show quoted text -

Well, the system has run all night and all day with no issues. I guess
thats that. Thanks again Paul and GBM, for you positve advice-J