Since summer is back here, I am a bit wondered about the temperature of my CPU. It has happened a couple of times that when I reboot my computer, the POST screen shows an error message : "Hardware monitor has found an error". Obviously this error is concerning the temperature of my CPU, an AMD Athlon XP 2000+ running at 1.67 GHz (not overclocked).

At any time, I noticed that the temperature of my CPU is about 50 °C higher than that of the MB... for instance, right now as I'm writing this message, Asus Probe 2 reports a CPU temperature of 74 °C and a MB temp of 24 °C. During hotter days, when MB temp gets around 30 °C, my idle (!) temperature can even reach the 77-78 °C ! Now I'm not sure this is all right...

Running 3DMark03 during about 45 mins the other day got it around 89 °C... so I don't feel really safe when playing games anymore!

It is reported on the following web page that the max temperature supported by my processor is 90°C :
http://www.heatsink-guide.com./maxtemp.htm
But I have seen many posts reporting temperatures in the 50 °C for processors like the 2200+ or 2400+...

By the way, I have 2 supplementary fans installed in my case, 1 at the front and 1 at the back, plus that of the power supply... MB temperature doesn't seem to be an issue, since it never really gets over 33-34 °C.

Some information about my MB and BIOS, that I got from Asus Update V3.29.05:
Model: A7V333
Version: VT8367/VT8233A
Chipset: ASUS A7V333 ACPI BIOS Revision 1006
Date: 07/17/2002
Onboard Sound: None (woa)
Onboard Lan: None (wol)

I also have the original, AMD retail fan installed on my CPU. Asus Probe reports it is spinning around 5100 RPM.

It's also been almost one full year since I last opened my computer, so I would suspect dust to have gotten into the heatsink and/or fans... maybe that would be my problem?

Does anyone have any other ideas?

Not much you can do except to leave your case open or buy some case fans maybe a new hsf or consider a new case. Dust will raise your temps but not much. And then there's water cooling.

The retail HSF should be OK, especially since you're not overclocked. You didn't mention anything about case fans though...if you don't have any, I would suspect that is a big part of your problem. You should have a minimum of 2...one in the front bringing in fresh air, & one in the back taking out the warm air. Leaving the side off your case as suggested by Kev may help some, & others posters (johnoh especially) have suggested placing a room fan blowing into the open case as a temporary fix.

Is that the latest version of Asus Probe? I know I was getting some odd temp readings on my Asus A7V133-C mobo using an older version of Probe...but the temps reported in my BIOS & thru SANDRA were good. I went to the Asus website & downloaded/installed the latest version & now they're all reporting the same temps.

You also might wanna install cooling software such as CpuIdle. It lowered my idle temp by about 10C...it has no effect on temps under load though...

the older versions of asus probe are mis-reporting wrong....download the latest asus probe.....or... get a hardware temp monitor, forget the software...i just got myself a vantec nxp-101 multi function display, it comes with 3 temp sensors ( cpu,hard drive, case)a fan speed control dial, display of your cpu fan rpm and it fits in a 5.25 inch drive bay

my temps from the sensors i installed are about 2-3 degrees lower than what bios is reporting and the bios is almost dead on in the first place, so close enough

before i installed the sensors, motherboard monitor,asus probe and speedfan had given me all different numbers...the newest asus probe is very close to the bios, but i like my display better

amd 2500+
fan speed dialed down to 5450 rpm
cpu temp is 38 c
inside case temp is 27.5 c
hard drive temp is 23.5 (2 inlet fans blowing on hard drive)

open that thing up and blow it out with a shop vac or canned compressed air....dust insulates, keeps the heat in, no dissipation

read post 3 again

One word of caution about using a shop vac...make sure you BLOW the dust out, don't vaccuum it out...the vac can cause static

I don’t think your temps are accurate. If you were running at those temps your computer would be freezing up most likely.
I do think you need a high quality heatsink. The AMD approved heatsinks are barely adequate. I’ve had two and neither one would keep my cpu from overheating. There are heatsinks available that will keep your cpu 3 or 4 degrees above the ambient temperature of your case.
During the hot summer months you might want to turn down the bus speed to lower the temps till the cooler weather comes back.

IMO, if you're not gonna overclock, don't waste your money on a new HSF...the retail one will work just fine...it'll even suffice for mild overclocking

OK... I am running version 2.20.03 of the Asus Probe, which is, according to Asus' web site, the most recent one. The readings I get in the program also correspond with those I get in the BIOS at boot-up.

Yesterday I opened the computer and cleaned the dust inside it. There was a thick layer of dust between the heatsink and the fan. I removed the fan, cleaned the heatsink and put the fan back. Now my idle temp is somewhere around 65 °C and full load, 72 °C. Would that still be too high?

You should try running the computer on max load, keeping your case open. Use pifast or some other program. Try to put your finger on the heatsink. The heatsink should be almost as hot as your probe tells you the processor is. If this is not the case, change the thermal paste between your processor and the heatsink. I rely on artic silver III. (You should change it anyway)

I have tested the effects of artic silver III in comparison to the "bulk" thermal pastes. The cooling effect is 5-10 degrees. Its a cheaper way than changing the whole heatsink system.

My test bench is an old P3 550 running 632. With the basic thermalpaste the temps varied from 56 to 62 degrees. With artic silver the temps dropped in to 48 to 53. As you can see the sensor is not too sharp, but you can still see the difference.

If you are already using a high quality thermalpaste assembled as seen on the instructions on artics website I suggest you buy a new heatsink like I did a few days back. Zalmans 6000 series is pretty cool and not very noisy. It aint the most powerful fan/heatsink combination, but its silent and enough effective. With that athlon I would say the temps on max load should be around 55-65. I have the Zalman connected to Athlon XP 1800+ Full load temps are 53-55

Ofcourse these things are a sum of many factors and Im not unmistakeable, but I feel my suggestion is worth a shot. In my house the roomtemperatures are hardly ever over 25 (I live in Finland) With the exeption of running all my computers at the same time.

I have an old P3 550 and the athlon XP 1800+ as mentioned, plus the newest addition to my arsenal a P4 2,8 all these three running pifast at the same time will make my room heat up FAST.

I dont need to use the heaters in my house at winter tough it -20 outside :)

Updated my BIOS to revision 1007 and idle temps dropped from 67 °C to around 50 °C. Very strange... but kind of a relief :)
No full load temps are around 62 °C, no matter the MB temp...!