A question for technical types...

[tubedude]

I just tossed a system together, that Asus a7m266 thats been lying around here for 4 months (one of em) and an AMD 1ghz with 266 FSB.
I powered up, everything sounded nice, and right when I got my single no-trouble beep, I noticed the fan on the CPU wasn't spinning. I turned it off, it had been on about 20 seconds or so, and spun the fan around a few times. Didnt feel stuck or anything. I turned the power back on, it spun once, sat a second, spun again a little, then stopped. I never noticed the other ones doing this, not that they weren't, maybe I wasnt paying attention. Anyway, I changed the fan out, and it did the same thing. Now, I was assuming the CPU fan would come on and stay on, considering the heat that these things produce. Is there a problem, or will it come on if I wait a little longer? I'm scared to let if go much past the beep. They overheat fast. Just wondering if it has a heat sensor that turns the fan on and off. Anyone know anything? I've always seen the fans come on directly. I know there is a temperature guage on this motherboard, and I wonder if it has anything to do with it.
Anyone?

 

[db51]

Ouch... an Athlon without a fan...Now that's bad...As you said the Athlon overheats very fast and it does NOT have an overheat protection ( the motherboard probably has one but you have to configure it in the BIOS) so don't let it run without the fan spinning!!
I would suggest checking the power supply and that the CPU fan is hooked up properly. Anyway the fan should be spinning AT ALL TIME, this in an Athlon we're talking about!

 

[Dolemite]

What kind of heatsink/fan is it? Most mobo's can turn the CPU fan off but only as a power saving feature when the CPU is idled, but I can't imagine anything like that being the default setting in the BIOS. I would try another heatsink/fan, one that you know works and see what it does. Also, check the wires to the fan, there may be a short or something, but I would guess that the fan is faulty.

db51 and you're suspicions are right, you shouldn't let it run even for a couple seconds like that. Those AMD chips run hot.

BTW, some HSFs have thermal sensors but I bet you'd know if you bought one. Also, you might want to try removing the CPU and leaving the fan plugged in and booting the system just to see what happens.

 

[tubedude]

123

Damnit, suck my balls. I have an email into tech support at AMD and Asus. I tried 2 fans, both did the same thing. Might be a power supply problem. I hate it when shit gets harder than it oughta be.

 

[Dolemite]

Damnit, suck my balls.

Well said....but no thank you!

What I would do it just wire the CPU fan into one of the power supply plugs, bypassing the motherboard and whatever it might be doing to control the fan or any problems in the motherboard itself. If you don't have a 3-pin to 4-pin adapter, all you really need to do is just cut the 3-pin off the end of the fan wire, strip a little wire, and stick the ends of the bare wire into a female Molex power supply connector. Red (or yellow) on the fan wire should go to yellow on the Molex, and black on the fan should go to black on the Molex (the black that's next to yellow). I know this sounds a little flakey, but just jam the wires in there good and tight and then wrap a little electrical or duct tape around the connection to hold it together and you should be good to go. I've had a fan running like this for at least 2 years with no problems, and I'm always up in my case swapping cards around like nobody's bidness!

Forget about tech support, they are consistently useless.

 

[tubedude]

123

Well I have a plan... I'm gonna keep the case open and upright, turn on a mega fan directed into the case, and fire it up and mess in the bios for a bit. It has temp monitoring and fan rpm monitoring and all kinda stuff. Nice mobo, for real. I alkways recommend it. Maybe the fan will just fire up after about 30 seconds and I'll feel much better.
P