Desktop computer cooling issue

Joeaksa · 05-11-2010, 07:41 PM

Gents,

Am pretty good with computers but this one has me scratching my head.

Have a Dell desktop, about 2-3 years old. Been running like a charm, in fact its been on and running about 99% of the time I have owned it.

Started freezing up yesterday. Had an idea that it was getting warm inside so opened it up and put a external fan blowing into the unit. Worked fine. Then installed some motherboard monitoring software and yep, one of the video cards is getting hot and shutting things down.

Head to Fry's for a new fan. Its a standard 92mm version but the new one has a high, medium and low switch and loads of ball bearings.

Put it in on the motherboard connector and turn the switch on high. Boot the computer and fan works great for a couple of seconds then reverts to low speed. Chit! Temps go right back up into the red. I plug the fan into an extra computer power supply I have and it runs nice and fast when I do this.

This fan plugs onto the motherboard with a small three pin connector. Am guessing that something on the MB or BIOS is telling the thing to run slow when we really need it on high.

Anyone ever encountered this and whats a work around? Problem is that this computer has SATA connections on the power supply, otherwise I would hook the fan up directly there.

Ideas?

Thx,

Joe A

ODDJOB UNO · ODDJOB UNO's Garage

silly.......................YOU NEED A RADIATOR!

Joeaksa · 05-11-2010, 08:53 PM

Nah, aircooled all the way for me!

jyl · jyl's Garage

There must be another power connection in the computer that you can use, with a Y cable if something is already plugged into it?

Joeaksa · 05-12-2010, 05:13 AM

John,

Was thinking the thing but so far cannot find an adapter that goes onto the SATA hard drive power cables for power.

The fan came with the old fashioned four post power cable.

My heartburn is why does the puppy plug into the motherboard to get its power? Why does it go into high speed first then slow down? Even went into the setup on the motherboard to try to find a setting for this but did not see anything...

Thx,

Joe A

slakjaw · 05-12-2010, 05:34 AM

You could get a fan that plugs directly into the power sup?

chuckr · 05-12-2010, 06:02 AM

gotta ask... what is your cpu usagage ?
is your cpu over processing
task manager/ performance cpu usage

Jagshund · 05-12-2010, 06:14 AM

Have you checked the intake for dust? My Dell Dimension had a healthy coat on the front panel hidden from view that was causing the fan to run excessively. Clean it every month now and it's been fine since.

jyl · jyl's Garage

Do the SATA power cables come directly from the power supply, or do they connect to a regular four-pin (Molex) plug that leads to the power supply? If the latter, seems you can insert a "Y" splitter cable into that chain. If the former, well you could splice something - see attached for ideas. It does seem odd that there isn't another power plug somewhere, what was supposed to happen if you wanted to add a second graphics card or another hard drive, is this thing not expandable?

SATA Power Adapters

It would be ideal to figure out why the mobo is turning down the fan speed despite the temp sensor showing hot. But sometimes "ideal" isn't worth it.

Joeaksa · 05-12-2010, 07:32 AM

Well everyone, feeling more and more that its not just a cooling issue.

I "hot wired" the fan to a power supply plug and while it works ok its not on high speed either.

That said, even with more air running through the case am guessing that I have a bad video card. Evidently one card is getting hot. The temp readout for the cards (I have three video cards in the MB for three flat screen monitors) started at about 98c and is now up to 136c, which is pretty hot.

CPU useage is very low, running under 5% most of the time with spikes up to 50% or below. Do not believe that this is being caused by a hot CPU. Temps on the CPU and MB are ok, hovering under 50c but steady.

The graphics readout is now up to 140c and no signs of slowing so now its time to figure out which card is dying... time for the digital IR therometer!

Thx,

Joe A

Joeaksa · 05-12-2010, 07:35 AM

BTW, Dave, got your MSG this morning and tried pulling the one white wire. The fan ran but at the same speed. ???

Neilk · 05-12-2010, 07:45 AM

Joe,

Do you really need one video card for each monitor? On my old PC at home, I have one card outputting to two LCD monitors, one via VGA and the other via DVI. Unless you are an avid gamer, that should work fine for normal browsing.

Neil

Joeaksa · 05-12-2010, 07:49 AM

Neil,

Just checked and was wrong. Have two video cards in the puppy and running a dual output on one of the cards.

Am addicted to triple screens (would have 5 if I could!) and going back to two would be like driving a VW Beetle after having a 911 for all these years.

Just check the temps on the dual video card and its running 240f on the heat sink area, while everything else in the inside of the computer is a cool 100 degrees or so. Am guessing that the video card is tits up... and overheating, which is causing everything else in the case to get warm.

Thx,

Joe

Joeaksa · 05-12-2010, 08:17 AM

Well, now have found the problem for sure!

Took the video card out and it was right there.

The plastic fan on the heat sink for the video card had not been working for a while. Wires fallen off of the fan unit and fan itself covered in dust. That would do it!

Now to see if I can find a new fan for the heatsink or if I have to buy a new video card...

Joe

nota · 05-12-2010, 08:19 AM

what video card ?
some are known hot runners and have aftermarket fans available that replace stock fans
to keep them cooler
check the power wires to the cards swap power wires between cards
if there is a voltage drop the amps go up and so does the heat
and try the other card with the two monitors and the hot one with only one

Joeaksa · 05-12-2010, 08:22 AM

Its a NVida I believe. Not sure which model.

The wires going to the fan on the heatsink are baked, so its been really warm there. Just got the sink off of the board and the fan is replaceable, if I can find one that fits and so on.

Otherwise will just get another video card...

MysticLlama · 05-12-2010, 08:24 AM

Just get a new card, coolers are often in the $25-50 range, and I just recently bought a few dual DVI ATI cards for $39 that have big heatsinks and no fans on them, thus no noise and nothing to break.

jyl · jyl's Garage

Multi screen is the way to go! Too bad it is the dual card that is crapping out. I run triple at work and would like four, five, you name it.

rnln · 05-12-2010, 08:55 AM

External oil cooler then :lol:

Quote:

Originally Posted by Joeaksa

Nah, aircooled all the way for me!

Schrup · Schrup's Garage

Quote:

Originally Posted by Joeaksa

Just got the sink off of the board and the fan is replaceable, if I can find one that fits and so on.

Otherwise will just get another video card...

If you replace the heatsink, be sure to use a little thermal compound between the heatsink & the processor. If the card got that hot, it may be toast. If you have to replace your video card, check compatability with the Dell.