Fan overheating problems ASUS

This has been going on a bit, thru two Os's--XP, then Vista--and have an ASUS P5GC-MX/1333 motherboard, and have the PCprobeII, so I can check temp/speed, etc...and it runs cool enough--around 35-45c, as long as I have the *q-fan- disabled, but of course, kind of noisy(cpu fan around 25-3000rpm)...so I go to bios--and enable q-fan, set it to "whatever" and save settings, and exit cmos...

Then before I even get out of bios, I get the "CPU fan error" and then will go ahead and boot up, but *then* my computer does quiet down, and it's really nice for about 5 seconds, but watching my pcprobe, I always see my fan speed drop *way* down, around 5-600rpm, and at the same time, my cpu *temp* starts up around 60+c, and I've got an xtra thermaltake fan, that's about new, could *that* be thre problem?

I'm plugged into correct spot for "chassis fans" on mobo, right next to where cpu fan plugs in, but I think that's cool...what am I missing?

TIA

 

I really appreciate the help on this, I just started working, really, on hardware this year, and built now two pc's, and of course, an all obsessed with everything...

I ran way too hot, I think at first, always over 60c, and after reading some posts on here, cleaned up, and put the thermal paste on correctly, and it actually dropped about 10c, and then my fan did seem to be running o.k., but for some reason, then started running pretty low, and the temp creeping way up, and the bios kicking in "check cpu fan" and so I finally disabled the q-fan setting, and it shot up much faster, and noisier, and cooler, which is a trade-off I'm o.k. with...

But I haven't checked yet the things you said: I *did* put in new fans recently, on the front, and this case is an--shoot, I can't find the name...well, it's kind of late, so what I'll do is check all the fans tomorrow, and get the case name...for some reason I think it was an "antic" case, with clear acrylic on one side, (looked good to me in store, but kind of cheaply made) and a fan blowing straight at cpu, another in the back blowing strait at cpu, and the two I also put in, in the front, blowing in, on the bottom, right at the hardrives...so doesn't seem *any* of the fans are blowing out...tho it's pretty airy, and not a totally mico size, but sort of a medium tower, and I did kind of lean up the cables, they are sata, except for dvd...not sure if I even have camera, tho I once did, selling junk on ebay, when that was all new and exciting to me :-D

 

The bolded part doesn't sound right, the fan at the back should blow out, air should go in one direction, front to back and out. I don't know what CPU you have but 60C @ idle is way too hot for any CPU.

 

Augie is dead on there. You generally have the front fans as intake fans (blowing cool air into the case) and the rear fan(s) are setup as exhaust fans (blowing hot air out of the case). If you look carfully on the side of the fan, you should see 2 arrows. One indicates the direction the fan blades spin the other arrow indicates the direction of the airflow.:cool

 

Thanks for all the replies: what I'm doing today is checking all the fan directions, and then since I have a spare thermaltake fan, and love "messing" w/the paste, once I figured out--on here--how to put it on, I might try the other fan, "just in case" as when I *first* put it in, it seemed to work perfectly, adjusting speed to "quiter" if I put it on "optimal" of the three q-fan choices in my bios...

And I had read on here about making sure fans blew in, in the *front* which was where I put in fans, right in front of my two hard drives, which I have right on the bottom, but it does appear as if the *top* fan, in the back, is also blowing in, straight at the cpu, and also, I'm not sure if I described it right, as the *side* panel, which is clear, *also* has a cute blue fan, blowing straight at the cpu, which I like looking at at night, haha...

but anyway, again, thankyou all for your help, and I'm going to see if those things don't help it, as I agree, 60c is too hot, but naturally, I just turn off the q-fan, "enable" and that way it just blows really hard, and keeps it fairly cool....

 

The side fans should be blowing in but the back has to be blowing out, just like the power supply.

 

Just a quick update: I did change a fan around, now front blow in, and back blows out, and side fan, still blows on cpu fan, and that seems fine...

It does appear that there was some sort of conflict between my fanspeed settings on PCprobe, and my bios setting, so I turned q-fan back to "enable" in bios, and this time set it to "performance" which is faster than "optimal" and also made sure pcprobe was set to same, and now it *does* seem to be working, and temp stays around 50c, and fan speed hovers between 700-1000...and that seems cool, so all is well: again, thanks again, always get help here when I'm out of ideas, and do appreciate it...

 

Good, a 10C drop is significant but I still feel that 50C is still too hot with all the air that you're pushing through. Do you have an AMD CPU as those do run hotter than Intels, but my X2 @idle was around 40C with only one fan out plus the PSU. Oh, try another temp monitoring app like HWMonitor just to doublecheck PCProbe. There are folks that don't trust it but I found PCProbe accurate.

 

Glad you got it cooling better!

 

Yes: I think I'm getting closer to sorting it all out...I know I've bumped into several of you before when talking about thermal pastes and such, but--probably since I'm sort of new to hardware, and have only built a couple of pc's, just this year--I got excited when I finally noticed that I could actually monitor and even lower the heat in the cpu, and hard drives...

I had always noticed that storebought pc's were *quieter* than "home-made" pc's that I had bought or made, and it bugged me, because in *every* other area, I found non-commercially built pc's to be better, simpler, and cheaper...so this year I started trying to figure it out, and anyways, I'm going to try another temp monitoring app for a few days, as that *might* be why this one still stays up around 50, or when it drops *beneath* fifty--which it does--the fan *immediately* drops down to around 3-500rpm, turning on the "red" alert and all that, and I tried setting it differently, but that is when my problems began, so I'll keep checking...

Again, thanks to all of you, who have been sort of educating me in this area...

 

Your description makes me wonder about the temperature-control calibration for that fan.

Generally, the idea is to run the fan no faster than is needed to keep the CPU temperature under a given limit -- but I agree that 50C is too high unless you're gaming, or you've overclocked the machine, or the room (ambient) temperature is above, say, 25C. The control circuit shouldn't be cutting the fan RPM back that far until the CPU temperature has dropped below a much lower limit -- perhaps something like 40C.

Once you get that sorted out, you might want to reduce the alarm threshold for that fan so that 500RPM doesn't generate alarms when the fan should be running at that speed. If you're using ASUS PC Probe, you have the ability to set alarms based on CPU temps as well as fan RPM. The fan RPM alarm is really there to let you know that the fan has stalled -- maybe because of a frozen shaft bearing. When that happens, you do want to know that before something overheats.

Ideally, the fan RPM would rise with CPU temperature. Like, 500RPM at a CPU temp of 40C, and rising to max RPM as needed -- say 50C. In other words, at some intermediate temperature, the fan would be running at some speed between 500RPM and max RPM. That way, the fan would always be delivering what's needed and would never be noisier than it needed to be. Unfortunately, matching the fan's performance to the heatload isn't a simple matter without some pretty complex control circuitry. Usually, it's just guesswork where you and I are concerned.

However, I'd have thought 500RPM was pretty slow for most CPU fans. Those fans tend to be small to fit on the heatsink, and they therefore have to turn faster (and be noisier) to push enough air through the heatsink. What kind of a CPU heatsink have you got, and how large is the fan?

 

Yep: I agre with you, and I've fiddled with it a lot, but still, it seems kind of erratic, and when it gets down beneath 50c--which I like--the fan just drops *way* down, when I'd rather it stayed up around, oh, 1000 or so...but again, it *is* working, and doesn't go much higher than that, and I'm still fiddling with it...and it seems pc probe, won't let me set the fan speed alarm at *less* than 600rpm, and so I've got the red thing always kicking in...and of course I've got the sound turned of, if not I'b hearing alarms...but it seems to be doing alright, we'll see...

Right now, for example, temp is 48c, and fan is droped down to 470rpm, when I'd rather it stayed up higer, and maybe drop temp lower: it gives me three choices, and I have "performance" as that is the one it seems to run the fastest at....

 

Duckfeet, have you considered just hooking up the fan to the PSU and let it run at 100% all the time? I find periodic fan speed changes more annoying and distracting than a constant noise.

You could also hook it up to a fan controler. Some mount in the front where the optical drives go, and have a knob that controls the speed of the fan.

Of course I am used to PC noise that would drive the average person insane. Or perhaps I am insane and just don't know it.:-D

 

Yep: and I have, and then it stays *really* cool, and is, yeah, a little noisier...I think I just like trying to figure it out, more than anything else, and kind of enjoy watching the little pcprobe dealie show the cpu and fan speed...and it seems to stay beneath 50, but something does seem slightly wrong, and probably when I put this last tower together, I'll put the new fan on here, and maybe another fanspeed reader, and just see what it does...

But yep, for a while I did just what you said: just turned off--in BIOS--the q-fan, and it immediately sped up the fan, and cooled of the cpu...