Nice and low temps when idle, high temps when stressed, peltier/air

I have a second computer p3 700e slot 1 oced to 1035-1050mhz with an alpha p3125s and an 86w peltier, under idle the cpu is running -5c, but when I run 3dmark 2001 the temp jumps to around 25-30c, I have some sunon fans on the alpha now, I am thinking of getting the 38cfm delta's think that will help?

No I do not want to run water cooling.
Mark

the deltas will certainly lower the temps a whole lot. Those are high temps but nothing to cause alarm.

It could be a few different things, starting with more air may help but it could be a lack of voltage or amps or its possible the pelt you have is not big enough.

Sounds normal. May just be a smidgen high (usu 20c) but no problem. And yes, it may very well be a power supply problem.

It is also possible that your heatsink and fan can't get rid of the extra heat. When you stress your cpu your creating a lot more heat. That heat has to be dispursed by the heatsink and fan, It's possible that while idle your HSF is ok and can handle the heat load. But once you stress the cpu the HSF is being saturated with heat and can't get rid of it fast enough.

I would try some fans that move more air. Or maybe look into a larger heat sink with a fast fan. The copper HSF's conduct heat better so if possible get a new copper one.

I run a PIII 733 FCPGA with an 80w peltier. But I use water cooling. My temps are -10 idle and 4C at full load room temp in the low 70's F range. Last week when It was 95F in my room I was geting idle temps of -6C and full load temps of 20C ! Was having a hard time cooling down my radiator. But it shows how much of a difference air flow and the temp of the air your moving makes a difference on your cpu temps. The more cold air the better.

I agree with zoopa 100% in respect to the HSF not being enough. Pelts put off sooo much by themselves.
If you have access to an additional heat source, another pelt possibly, something that can "act" like a cpu, but will allow you to take several thermal readings. I did the following with my HSF/pelt and my waterblcok/pelt:
I used a 72w pelt to simulate the cpu heat, and 2 compunurses attached at several places: coldplate, pelt(s), waterblock, etc... I have a variable DC power supply, so I would increase voltage / amps to simulate "load-stress", and my problem was with the psu I was using!
If you have a friend with a strong PSU borrow it to determine if that's it. I didn't believe for a second that was my problem, until 125 bucks later. I had to kinda prove it to myself, ya know see it to believe it kinda thing
PS I'm now using a Swiftech MC462, and it's kickin!, but I will always use a high-power PSU, dedicated to any pelt in the system

Yeah it's most probably the HSF. Note that your HSF must be able to remove 100+ watts of heat, 85W of it from the pelt. Maybe you need something like a SK6 or Glaciator for your P3+pelt.

I have a slot 1 intel p3,
I am thinking of getting the 60mm 38fcm, or the 51cfm screamer delta's for my alpha p3125s.
I run the peltier off a second power supply.
It is a 300w with 12 amps on the +12v line.
I am running 3 120mm and 2 80mm fans on it.
The total draw on the power supply is 9.299 Amps.
I am pretty sure that the alpha is the best slot 1 heatsink.
I have one of the 120mm fans blowing out the air/heat from the alpha also.
sigh,
mark

mark said:

I have a second computer p3 700e slot 1 oced to 1035-1050mhz with an alpha p3125s and an 86w peltier, under idle the cpu is running -5c, but when I run 3dmark 2001 the temp jumps to around 25-30c, I have some sunon fans on the alpha now, I am thinking of getting the 38cfm delta's think that will help?

No I do not want to run water cooling.
Mark

Click to expand...

Those temps are not bad, but it sounds like your peltier is running at 5volts and not 12volts.

I use to run a Alpha PAL6035 with a 72watt peltier. on a PIII 700@1008 temps would be -15c idle and 20c load. Thats with the peltier running at 12volts. Now running at 5volts temps would be -5c idle 28c load

The P3125 is a bigger heatsink so it should be able to get rid of the heat faster.

hahaha,
I am 100% sure I am runnning on the +12v line

Here is something I am wondering now, how about running the peltier at 17v.
+12v line, and the -5v line .....hrmmm, i wonder if that'll pop the power supply.
anyone try this before?

anyone know where i can get the delta 60mm screamers?
38cfm, or the 51cfm.

You will still have 12 Volts
You will need to have a 17v power supply to get 17 volts!

Uping the volts won't help the pelt either. There set to run at optimum preformance at there specified specs. More volts won't mean a cooler pelt. Just a broken one.

I run a 80w pelt off my 300w deer power suply and the pelt is fine. I still think your HSF is where your problem lies. Your not removing the heat fast enough. I would try to get the bigest badest HSF you can find and give it a shot. I'm not fimilar with the Slot coolers so you'll have to ask someone else for recomendations on that.