reading CPU fan in Asus PC probe

Sorry for the long post, but tried to cover all possible bases.
Just assembled a new system and am getting periodic readings on the software--Asus PC Probe--that my CPU fan has stopped for a few seconds. My sys is all new, AMD-approved hardware:
A7V266-E, rev 1004b
mobo: jumper-free and BIOS defaults
newest AVI drivers
AMD 1800
Samsung 256M PC2100
Volcano 6Cu HS
Sparkle FSP350 PS
Enlight case with chassis fan
WD 60G HD
Win 98 (all service packs installed)
The Asus PC Probe software is set to install at boot-up. Periodically, and with no apparent pattern (ie, what might be a catalyst), I get a warning that the CPU fan has stopped. Monitor comes on screen and shows 0 RPMs, but just for a few ticks and then resumes normal readings of around 4720; threshold on software is 2200. HS is rated at 4550 /-10%. On software CPU cooling menu I have checked "always" on software cooling.
I've read about the inaccuracy of software reading mobo temps, so have basically attributed erratic CPU fan readings to software. Perhaps not?? When I had the cover off and it perhaps happened once, it was so short that I did not have time to visually check to see if the fan had actually stopped.
The idle/unloaded CPU temp is around 51C with room temps around 20C. I likely would not be concerned, but the other night while the machine was idle for awhile, I wandered into the room and saw the CPU fan montior ticking at 0 (not sure for how long) and when I checked the temps the CPU was at 57C, but then dropped to normal a few minutes later. Should I yank the top off and try to catch if the software is accurately reading? Are these temp/fan variances worth worrying about given the software? Should I make any setting changes to the software or BIOS?
PS. A public thanks to Larry for his how to guides. Been a few years since I assemble a computer and his detailed guides were about the best I could find. Made for a much less stressful assembling process.

1. RE: reading CPU fan in Asus PC probe
lbyard Jan-24-02 04:53 PM
In response to message 0

Look at the temp/fan in the CMOS Setup. It may take up to a half an hour to heat-up.
>Should I yank the top off and try to catch if the software is accurately reading?
Yes. The fan could have a bad bearing, the plug could be loose, a cable could be in the fan (I would think that would make some noise and make mince meat out of the cable).
“Keep your cotton-picking fingers away from the CPU fan! If you accidentally stick a finger in one of these turbojet engines expect to run to the bathroom with bloody paws! I like the Thermaltake cooler, but would also purchase a fan guard for a computer like mine that is left with the top off.”
Although below the maximum spec, 51C is high, especially for a volcano. Larry

2. RE: reading CPU fan in Asus PC probe
Berkobien Jan-26-02 11:29 PM
In response to message 1

Thanks Larry. After letting the machine warm up, I checked the CMOS settings, and then would boot up to see if PC Probe settings were identical. I did this at various times and it appears that the PC Probe and CMOS settings are pretty much identical.
The elevated CPU temp is disconcerting, so removed the chassis cover where I have three open,uncoverd bays and uncoverd chassis fan. The CPU temp dropped from 51C to around 45C in a few minutes. I have my system inside a computer desk where the front of it is completely open and the back has "pretty good" ventilation, I think, but I can improve it and will leave the chassis open until I know its better ventilated (my wife won't let me leave it out with no cover; the price you pay for marriage I guess). At 20C ambient temp, what would be an optimal unloaded temp for my system if 51C is on the high side?
Also, can see the CPU fan through the open bays. No cables intruding on the fan. After much waiting, the PC probe monitor warned the CPU fan stopped, for just a few "ticks" (maybe 3 seconds), but I was able to observe the CPU fan and it appeared to run fine, not even a slow down. I'll try to repeat this with the system in CMOS to see if those reading are similar.

3. RE: reading CPU fan in Asus PC probe
lbyard Jan-28-02 06:05 PM
In response to message 2

>"pretty good" ventilation.
I have seen this sort of problem before. There should be plenty of space behind the PC (at least six inches/15 cm) and ventilation into that space. Make sure the power supply fan is working (feel behind the computer where it exhausts).
45 deg C is still high for that heatsink-fan.
I leave the cover off my desktop case, brew beer in the kitchen, sleep on the couch when I feel like it, shave when I want to, etc. and have been happily married for nearly 30 years. She handles the money... Larry

4. RE: reading CPU fan in Asus PC probe
SceatUK Feb-12-02 04:59 PM
In response to message 3

Hi What a great site!
My cpu temp readings went up by 10c between two different versions of Asus PC Probe!!
Treat them lightly!!