Case Fan Direction

Ned · Post by **Ned** » Fri Dec 16, 2005 11:39 pm

Is the fan on the side supposed to blow into the case or out?

HeXetic · Post by **HeXetic** » Fri Dec 16, 2005 11:48 pm

It's your choice. Fans at the front blow in. Fans at the back blow out. If you have a two-slot rear-exhausting graphics card (like a GeForce 7800), you may want to have a side fan duct fresh air in. Otherwise, you may want to have it duct hot air out in order to prevent hot air from the graphics card from passing over the CPU on its way out.

Duper · Post by **Duper** » Sat Dec 17, 2005 12:35 am

From what I understand, you generally want more air blowing in than out. This keeps dust from being sucked in through all the cracks.

Also what Hextic said.

Cooling really is the issue and "these days" there is a cooling pipe for just about every component in your box.

Vindicator · Post by **Vindicator** » Sat Dec 17, 2005 3:12 am

I've always had my side fans blowing inward. The air coming in keeps the video card cooler than if it was just blowing air out the side.

rijruna1 · Post by **rijruna1** » Sat Dec 17, 2005 3:47 am

this coupled with a larger than normal low rpm fan would be one very quiet set-up dont you think?

http://www.performance-materials.net/ht ... 982000.htm

cheers
rij

BUBBALOU · Post by **BUBBALOU** » Sat Dec 17, 2005 7:26 am

The one on the side is to supply fresh air for the video card.
this on is usally in front of the card...

some bozos cut holes everywhere...

only the top(if you have one) and back are OUTWARDS

Ned · Post by **Ned** » Sat Dec 17, 2005 11:41 am

Thanks!

A PC I built for a kid is apparently promptly shutting off once in a while, like once per 2 weeks. I asked if it was during hard use and he said yes.

The case seems well ventilated, so I am suprised. If I get him on the phone, I'll suggest he load folding at home and see if 100% CPU duty cycle can increase the problem or not.

Currently my theories are:
Virus
some kind of MoBo temp wire not attached right
some kind of Cool/Quiet Driver not installed
Some App is not playing nice with windows

It's not overclocked and it's a good case; the heat sink is on right and running, so I don't really think direct cooling is the issue. Maybe the Main Power Supply (Antec) has a wire loose?

My other PC freezes essentially never.

HeXetic · Post by **HeXetic** » Sat Dec 17, 2005 2:47 pm

The most likely culprit for the situation you describe is a failing, ailing, or just plain insufficient power supply.

My present computer's second power supply, an Antec 550 (that I had to buy to power my 6800 Ultra), was failing to deliver sufficient voltage on the +5v rail, resulting in a computer that was A-OK to POST, and usually made it into windows, but hard-locked and had errors constantly.

Check the voltage monitors in your BIOS, or run a voltage monitoring tool in Windows as you perform HDD activity. If one of the rails drops, you've found the culprit.

fyrephlie · Post by **fyrephlie** » Sat Dec 17, 2005 11:32 pm

what hexetic said... if the psu is NOT QUITE powerful enough you can get random power loss on heavy loads.

of course it can happen due to over heating... also saw a similar situation when the motherboard was shorting on the case (the guy who put it together missed just didn't think the risers were necessary). can also happen if the computer just plain doesnt like you.