Power fan below threshhold

ReadyMan · Post by **ReadyMan** » Wed Sep 14, 2005 7:49 pm

My wife's pc started beeping today, and the Asus pc probe program flashed on the screen (she has an asus cusl2 mb). It displayed the fan monitor box and said the "Power fan below threshold" and also
0 value for the power fan.

I shut it down, cleaned out the box (it was dusty, with some cobwebs, but not horribly so), and put it back together. The same warning box and sound came up when I fired it back on. I closed the asus probe and the machine runs fine....but I'm wondering what to do at this point.

the machine is pretty ancient a p3 800 OC'd to 966mhz.

nothing else is overclocked, and its been running fine OC'd for 3 years or so.

The power fan is the fan in the Power supply right?

Should I replace the PSU, or is this a non issue?
I wouldnt even know about it, except that I installed the asus program when I installed the mb drivers....

thanks for any help.

RM

Krom · Post by **Krom** » Wed Sep 14, 2005 7:55 pm

I'd replace the PSU, or at least get the PSU fan working again. If it overheats it could be trouble for the system.

ReadyMan · Post by **ReadyMan** » Wed Sep 14, 2005 10:23 pm

If the PSU overheats, it'll just die...but it wont damage the rest of the system (like short out the mb or something like that) right?

Canuck · Post by **Canuck** » Wed Sep 14, 2005 11:30 pm

PSU goes it can take the whole ship down with it.
Seen it more than once.

ReadyMan · Post by **ReadyMan** » Wed Sep 14, 2005 11:44 pm

sheesh.
well, I've never changed a PSU. Any tips?

I bought this PC in 2000. as a recap, it's a:
p3 800
CUSL2 mb
GF4 5900 video card
512mb of cheap kingston RAM

What PSU should I buy (I'll probably go to comp usa and buy whatever they have there...)? ATX something?

thanks!

RM

Canuck · Post by **Canuck** » Wed Sep 14, 2005 11:55 pm

300-350 watts will be plenty. I prefer better brands than what are available at Compusa but it should suffice for your purposes.

There are 4 screws holding the PSU in, probably one of the easier jobs to perform. Just note the position of and the way the colours go on the plugs.

Be careful to align the plugs before trying to jam them on.

All in all you'll find it a pretty easy job.

ReadyMan · Post by **ReadyMan** » Thu Sep 15, 2005 12:37 am

thanks!
I'll pick one up tomorrow.

Theftbot · Post by **Theftbot** » Thu Sep 15, 2005 2:26 pm

Also which is very important is before powering up with switch or surge bar is make sure the p.s. is plugged in mobo.

AceCombat · Post by **AceCombat** » Thu Sep 15, 2005 2:39 pm

you guys forgot one major thing to check:

Is the fan actually monitored and is it really dead.... use your hand to tell the ultimate truth.

Krom wrote:I'd replace the PSU, or at least get the PSU fan working again. If it overheats it could be trouble for the system.

Krom, you of all people not to ask: "Did you put your hand near the fan slot? Is it blowing out warm air?"

my asus probe shows the same thing, but my PSU Fan is not monitored.

what kind of PSU is this? and is the fan monitored?

chances are if it WAS previously showing a PSU Fan Speed, then it is a monitored fan. for a 5 year old PC i seriosly doubt this PSU needs to be changed. plug it back in and turn it on. stick your hand behind your PC and see if there is warm air blowing out the PSU Fan slot. if there is, disable the Power Fan monitor, and continue to use you PC as normal.

Jeff250 · Post by **Jeff250** » Thu Sep 15, 2005 3:57 pm

Yeah, since PSU fan monitoring requires using an extraneous fan plug on the motherboard, it usually isn't done. Like Ace said, check if it's working or not.

ReadyMan · Post by **ReadyMan** » Thu Sep 15, 2005 5:17 pm

I havent taken it out of the case yet, but it's blowing air just fine...its not warm air though (mildly cool).
I visually see the fan moving fine.

"power fan below threshhold" is what the monitor says...so it recognizes that the fan is working.

I'm pretty sure it was monitored all along, especially since I havent done a thing to this machine in a long while (including looking for new drivers for the mb or a new Asus probe program for that matter).

I went by circuit city and the cheapest PSU they had was $68 for a 350

DCrazy · Post by **DCrazy** » Thu Sep 15, 2005 5:19 pm

What brand? You can get an Antec PSU from Staples for about the same price. Circuit City all around is a ripoff.

And then, of course, you could always use Newegg.

AceCombat · Post by **AceCombat** » Thu Sep 15, 2005 5:24 pm

ReadyMan wrote:I havent taken it out of the case yet, but it's blowing air just fine...its not warm air though (mildly cool).
I visually see the fan moving fine.

"power fan below threshhold" is what the monitor says...so it recognizes that the fan is working.

I'm pretty sure it was monitored all along, especially since I havent done a thing to this machine in a long while (including looking for new drivers for the mb or a new Asus probe program for that matter).

wrong, asus probe "ASSUMES" its a fan that can be monitored, when in fact it is not a monitored fan.

my PSU Fan works, and asus probe says its below threshold? does that mean my PSU is dead? no, in fact its working perfectly.

but it's blowing air just fine...its not warm air though (mildly cool).
I visually see the fan moving fine.

thats all you need to know that its working fine. case closed. turn off the monitor for asus probe and your "Threshold" issue goes away.

i bet, if you popped open that PSU, if you look at the wires to the fan, there are only two of them. a red one and a black one. VDC+12 = red Common/Ground = Black

a fan that supports RPM monitoring would have a third wire usualy blue or green, sometimes white.

I went by circuit city and the cheapest PSU they had was $68 for a 350

sorry to say, you just spent 68$ + tax on something that was working just fine

DCrazy · Post by **DCrazy** » Thu Sep 15, 2005 5:26 pm

Well that wouldn't explain why the problem just appeared, so it could very well be a failing PSU. Just because it's blowing out air doesn't mean it's blowing out as much of it as it should be.

AceCombat · Post by **AceCombat** » Thu Sep 15, 2005 5:29 pm

i got a test for you....

download Asus Probe.... and run it. does your PSU have a monitored fan? cuz if it doesnt, i guarantee you Asus probe will still give you a "Threshold" warning.

Asus Probe is no smarter or better than Motherboard Monitor or SpeedFan. it only interprets what your SuperIO Sensor chip is detecting. but since the Sensor chip is not feeding a PSU Fan RPM and it ASSUMES there is a monitored fan on the PSU, it throws that warning at you.

Mobius · Post by **Mobius** » Thu Sep 15, 2005 5:43 pm

Just go into the BIOS and disable the PSU fan monitoring!

ReadyMan · Post by **ReadyMan** » Thu Sep 15, 2005 6:25 pm

I can disable it from my asus probe...

I took it out of the case and its an off brand:
SPI Sparkle Power Int'l LTD Model NO. FSP300-60GT

cant seem to take the thing apart to see the various wires.

I didnt buy the PSU from CC.

I dont really want to put more than $50 in this machine, as it's just going to be a server after I get my new rig (I'm ordering it last week of Nov.)

Matrix · Post by **Matrix** » Thu Sep 15, 2005 7:00 pm

ReadyMan wrote: I took it out of the case and its an off brand:
SPI Sparkle Power Int'l LTD Model NO. FSP300-60GT

off brand?!?!

Sparkle is the same company as Forton, hence the model number FSP = Forton Source Power.
Some of the best PSU's made.

The reason the PSU is pushing out cool air is probably becuase that PSU is hardly under any load with that system

That sparkle would probably run fine with almost zero air flow, I would just leave it. If anything replace the fan if you think it's not moving enough air.

And the heck with circit city, u can get a name brand PSU for that system on newegg for less then $30 shipped.

AceCombat · Post by **AceCombat** » Thu Sep 15, 2005 9:52 pm

Mobius wrote:Just go into the BIOS and disable the PSU fan monitoring!

mobius you asshat! the damn thing probably doesnt have a monitored fan!

Ready, did asus probe have a readout prior to this alert?

Jeff250 · Post by **Jeff250** » Thu Sep 15, 2005 10:19 pm

Or even just take a look inside your case to see if your power supply has any plugs going into any of your motherboard's three-pronged fan heads. If so, your sensor died. If not, you never had a sensor to begin with.

ReadyMan · Post by **ReadyMan** » Fri Sep 16, 2005 4:36 pm

I'm pretty sure (60%) that it had a readout of OK in the monitoring page.
I havent done a thing to this pc, including cleaning it, in over a year (wait..hmm. I bought a 21" sony monitor for it 2 weeks ago, and replaced my existing 17" sony with it. that's the only change I've done: unplugging the old monitor and plugging in the new one.).

The monitor should pull more power though... (it's a Sony 21" E540)

I dont think the sensor is busted, since it rates the existing fines just fine.

AceCombat · Post by **AceCombat** » Fri Sep 16, 2005 6:48 pm

okay, if you think it had a readout, you need to find the 3-wire cable that leads to a MB connector for a fan. like i said earlier, the colors are most likely going to be:

RED=VDC+12BLACK=COM
Blue,Green,White <-- (any of these is posible)=Signal

Krom · Post by **Krom** » Fri Sep 16, 2005 6:52 pm

A PSU fan monitor header will only have one wire for obvious reasons.

AceCombat · Post by **AceCombat** » Fri Sep 16, 2005 7:02 pm

uuuuuuh......... wooops

thank you krom.