do bottom mounted power supply cases provide enough air to the power supply?

[nx02nx02]

alot of the newer higher end cooling cases seem to now have bottom mounted power supplies.

Doesn't this design kind of starve the power supply for air? With the power supply intakefacing the bottom of the case there is like barely any room for the power supply to get air?

Maybe im wrong because I haven't bought one yet but my power supply was $200 new and I don't want to take any chances.

Is the general idea to flip the power supply upside down or? I see alot of pictures of peoples Cooler Master CM690 cases with the intake facing downwards and I wonder if their power supply is getting nearly enough intake air?

 

[Tullphan]

I've no problems w/my CM690 & Corsair 520HX. Good ventilation & is sitting approx. 1" off the (hard) floor. Shag carpeting, perhaps could cause a problem. I can't answer for the other cases as i've not seen them personally.

 

[MichaelD]

I see a lot of pictures where people flip the PS upside down when it's mounted in the bottom of a case like the P180. This is a mistake. Heat rises. The power supply is designed to have the fan pull air in from the bottom then push it up and over the heatsinks and other components inside the PS. The heatsinks can't do their job as effectively if the thing is upside down.

As long as you have at least 3/4" or so of room under the fan for air to get in you're fine. The P180 has 3/4" of space. I've had the case for over a year and have had no issues at all w/the PS.

There's a second part to this equation though. In order for the PS to pull in air, there has to BE AIR in the first place. In the P180 there is a fan between the PS and the hard drive mounting area. This fan pulls in air front the front of the case, over the hard drives and to the power supply.

Some people remove this fan b/c the space is tight b/t the fan and the HD wires. I'll admit, it's a giant PITA b/c the fan is "right there" and you've got to be careful w/the HD wires. If you remove the fan, you remove the cooling for the HDs and the PS. Relying on the fan inside the PS to pull in the air is a bad idea b/c PS fans are speed controlled, depending on the temp of the PS and/or current draw. If there's no supply of fresh air, your PS could overheat.

OK, that's enough jabber from me.

 

[Zepper]

The 690 has a vent grill right below the PSU, the others you mentioned provide other methods of providing air for the PSU. The above tips are good too. I'd like at least an inch of clearance, but 3/4 is probably adequate.

.bh.

 

[Throckmorton]

Originally posted by: MichaelD
I see a lot of pictures where people flip the PS upside down when it's mounted in the bottom of a case like the P180. This is a mistake. Heat rises. The power supply is designed to have the fan pull air in from the bottom then push it up and over the heatsinks and other components inside the PS. The heatsinks can't do their job as effectively if the thing is upside down.

Heat doesn't rise. Warmer air floats on top of cooler air. This is irrelevant when air is being pulled through by a fan.