Recently upgraded to a P5K-E mobo and zerotherm CF800 cooler with my pentium 4 (stock speed). In the bios, it says cpu temp at 46c and increasing about every two seconds until about 51.5c. Is this running too hot? CPU fan rpm stays around 900 rpm. Should I return the cooler and pick up a different one? Used AS5 for paste, maybe I messed it up on the installation.

Reseat it... Check that you put the paste on right

 
 
which p4? be more specific. i think, you are ok.

P4 LGA775 3.0ghz HT, couldn't tell you the FSB off the top of my head.

Hmm...Is it the old 90mm or the 65nm P4? What's it stock speed(ghz)?

It does seem a bit hot. You should make sure your heatsink is seated properly. I have a system with a P4 641 (65nm 3.2ghz) @3.687 using the stock heatsink/fan. It's 38c Idle/56c full load.

-Edit-
Yeah, that's high for 3.0...although the 90nm ones may run that high for all I know... If it's a P4 631 it should be running cooler.

_Edit Again_ I meant 38c idle, 44 was my system temp

I believe it is 90nm. Also, when installed the heatsink, it was slipping around so that might have screwed up the thermal paste layer that I applied.  
 
I am using the Asus BIOS to view the temps. I did not flash the bios yet either, so there may be a problem with that also. The CF800 cooler is only running at 900 rpm, because it auto detects temps and adjusts.

If load is 51.5C, its all good!

I believe 51.5C is idle, says the BIOS.

You need an application like Speedfan to check your full load temp. As long as you can keep under 65c at full load, it shouldn't be a problem.  
 
http://processorfinder.intel.com/D [...] Spec=SL8Q7
 
The thermal specification of all the 630s are 67.7c.

60C or less under load is best.

mine is idle at 46C 1300rpm peaks at around 54C around 2.8k to 3k rpm
 
i got P4 531 3.0Ghz

now check out my P4 3Ghz HT
http://cid-1532ae9d192e3fbe.skydri [...] dying%20PC
 
look at the load temp core the core!!!you will be "impressed"!!!LOL

Okay, does nobody here know that the motherboard temp monitors are not super accurate in the first place?

yeah i know.becasue HWmonitor recorded at 93C in one of the screenshot. but after i lapped both the CPU and heatsink at 100% load 2 threads it never go above 65C in all the temp monitor software.

Ok, so the ZEROtherm CF800 throttles its fan speed based on the temp sensor in the heatsink. I believe this is what is allowing it to hit 51 C on idle because the fan RPM is sitting around 900 rpm. Can I assume that it will hit around 2000 rpm under load to keep it under 60 C?

^
That sounds about right.  Also, I don't know about anyone else, but I've noticed that when monitoring the CPU temp in the BIOS, it will actually be higher than when idling in Windows.  I'm not sure why exactly, as I doubt the BIOS really puts "load" on the CPU, but my theory is that the BIOS is such a low level GUI that much of the CPUs features, like HALT states and other idle power savings routines are not utilized during viewing of the BIOS, increasing CPU power consumption and thus raising the CPU temp higher than what it would be while idling on the Windows desktop.  
I've tested this theory and verified a corresponding increase in system power consumption while inside the bios vs sitting idle in Windows.  With my Pentium D 805 rig, the difference in power consumption between BIOS and Windows desktop was 15 watts.

yes even the latest extreme processor. as when the sysytem is in BIOS it will need to monitor various component so therefore there is a load on the CPU. as the old say said, dont judge a book by its cover.dont say something looks basic and still use up CPU power.

Update. With around 70- 80% cpu usage, it runs at about 58C with 1022 fan RPM. I think I may have a problem. Should I re-do the thermal paste and reseat the heatsink?

that temp sounds right to me for that cooler. that fan speed is slow.

I know. I am thinking about returning it for an AC Freezer 7. But as long as I leave it at stock speed I should be good right? Or will the high temp kill my cpu? Idle is around 45C with 780 rpm on the fan. I hope ZEROtherm knows what they are doing when they designed this. Gets me kind of worried.
 
EDIT: I bet this thing was cookin' with the Dell cooling setup. All they had was a duct with a fan blowing air through the fins.

i think the AC 7 would do the job better to bee honest.

I would too, but I hear the AC7 is pretty noisy. I just ran prime95 for like 5 minutes and the cf800 seems to keep the cpu under 60C at around 1200 rpm or so. I think it is targeted to keep it under 60.
 
EDIT: You know what. I remember installing this thing and having one side of it lift up after I started screwing it into the backplate. If it already touched the TP and lifted up/moved around, would that create air gaps in it? that might be my problem right there.
 
Again, CPU is Pentium 4 530 (90nm Prescott). Prescott is notorious high temps if I recall.