PIII550E temp readings using Kaams Motherboard Monitor 4.17

[techwanabe]

I've been using Van Kaams Motherboard Monitor 4.17 TSR to check my CPU temperatures in degrees C. I noticed early on it seems fluctuate alot.

Anyway, it seems to read upper 30s to low 40s when I'm clocking at the stock 550 mhz. When I OC at FSB 133 giving CPU 733 mhz, then it seems to hover in the low to mid 40s most of the time which seems acceptable. I'm running my PIII 550E at standard core voltage, no tweaks and using the stock fan.

Today while I was running some computer training software which runs like a slide show and puts not stress on the CPU, I noticed the temp hovering around 54 degrees. That was strange and it seems kind of hot.

Why would the temp go that high when the CPU should be basically idling? My apartment temp stays around 70 degrees F all the time. Is that monitoring program not a very accurate? I dropped my CPU back to 550E to see how it would read and it is back to upper 30s C (~37 C). Heck, I'm not upping the voltage at all, so why the difference. Comments? Analysis?

 

[Mikewarrior2]

hmm... even if you don't change wattage, the chip is gonna run warmer at the higher overclocked speed.

In most cases, it won't run that much warmer, but since you have a 550E, the retail heatsink that came with it is sort of puny.

Also, what kind of case cooling do you have? And what you may want to consider getting a different heatsink(i'd recommend a taisol unit, better performing than a golden orb).


Mike

 

[Gunslinger]

I dont trust monitoring software. I use it as a gauge, but I prefer external probes with LCD readouts.

I am running dual P3 500's @ 560 mhz in my server and using Vantec 5030 fans. Temps are around 35c idle and 40c under load. Thats the rear cpu also, since it is the one that has the least air getting to it.

The Monitor program fluctuates a little but not much.

 

[Mikewarrior2]

Gunslinger,

he's using a p3 fc, with a diode-reading mb/slotket combination. As was done by a review last week, internal diode readings are more accurate than lcd-equipped thermistors. The reason for this? Thermistors are not isolated from outside air contact. At load, the thermistor versus diode reading varied by as much as 12-15%, which is significant. If available, internal diode readings are more accurate than external probes.

However, on your socket A setup, an lcd/thermistor is much more accurate than the under socket thermistor, since socket A cpu's do not have an internal diode.


Mike

 

[techwanabe]

Mikewarrior2,

Could you explain the working of temp readings? Are the readings I'm getting way off or at least ballparkish? I don't understand too well how the hardware works here for getting temperatures.

Well, I was kind of hoping to get this to OC without 3rd party cooling devices. Might I ask what an inexpensive heatsink and fan solution would be. That is something modestly priced which offers significantly better cooling performance without being overly large or exotic. I might be save going with what I've got, but a little insurance policy wouldn't hurt.

BTW, is it pretty universal that the PIII 550E can OC to 733 mhz? Seems like I read months back there was a general consensus on this, and in most cases with stock fan and voltage settings. BTW, I've got a generic mid tower ATX case with just one case fan in it.

 

[Mikewarrior2]

I'm am just a beginner newbie trying to understand the dynamics of temp measurement on cpu's, so i'll try to explain what i do know.

On P3s, intel has a built-in internal diode that measure's cpu temp. Unfortunately, you need a mb that properly reads this, along with a compatible slotket. On certain p3 mbs(most notably, most VIA based P3 boards except for Asus/Gigabyte models) use an on mb thermistor to measure cpu temp.

The problem is with the thermistor. They take temp neither from the cpu, nor anywhere near cpu core. Hence why thermistor readings can be written off accuracy wise(on any mb).

However, internal diode readings can vary from mb to mb(inconsistencies with how a mb reads the diode)and vary from cpu to cpu, even thermodiode temps are hard to compare between two different computers. So diode readings can vary with a + - of 3C.

As far as your temps go, you are reading the diode, and i'm guessing that at 733, your retail heatsink just isn't cutting it anymore. At that point, your cpu is putting out too many W of heat(roughly 18) that your heatsink can handle. Intel has 3 different retail heatsinks for p3(that i know of, a smaller one for the 500-550E, a medium one for the 700-866E, and a huge one for the 933). I'm guessing you have the smaller one.

You might want to try either a gorb, or to get in on the Taisol CEK*** deal in the hot deals forum. If you do get the taisol one(it performs better than the gorb) you will need to loosen the clip a little bit.


Mike

 

[techwanabe]

Mike, Thanks much for the explanation. I'll check out the heatsink/fan combo's you mentioned. So it sounds like the readings I'm getting are probably in the ballpark, is that what you are saying?

I'm wondering why the heat readings have climbed. Athough I haven't watched it closely to see it is a trend or something I missed. I didn't start OC'ing until that last couple months but I don't recall seeing anything like 54 degrees C until recently. But even at 550 mhz, I was getting readings into the mid-40s so that is probably consistent with the OC temps I'm now seeing.

In your opinion, is 54 degrees C too hot to run regularly? Should I drop my speed back until I get a better cooling solution?

 

[LegionX]

i run a 550 @ 803 and it runs idle at about 39c to 42 c and under heavy load can get to 60c , thats using hmonitor pro. thing is when i am in the bios it shows it starts at 50c plus and totally scares me but everything runs fine and if you go to intel they show that the 550 can work ok all the way up to 80c so i have stopped worrying and wont worry til i start seeing problems.
i think that on the bios it is messed up - i am using a asus p3v4x board and alot of others have had the same temp readings and only conclusion is that it is messed up.
anyway make sure you have sufficent cooling and dont worry about it unless it really gets high.

 

[techwanabe]

LegionX

"if you go to intel they show that the 550 can work ok all the way up to 80c"

Wow, Intel says up to 80 C? My 54 degrees bothers me and that isn't pushing it hard either. (thats 130 deg F) I'd like to see the temp lower tho. I'm going to look at some replacement fans and heat sinks.

 

[Mikewarrior2]

Your temps are fine, but you'll definately benefit with a better heatsink... Something like a taisol unit will drop your temps to probably within 10-12C of ambient case temp(probably into the 40s for you).


Mike

 

[MrMike49]

Does the ABIT BX6 (ver 1) mother board read a PIII temp diode ? If so, how can I access the readings ?

thnx

 

[Mikewarrior2]

Check this site to see if your MB is supported by MBM. MBM website


Mike