Why are there so few computer cases that put the PSU at the front?

4

I am going to buy a new computer but I am having difficulty choosing the right case.

It will be put in a place similar to this one:

enter image description here

where the back is closed, making the PSU not suitable to be placed at the back (in my opinion).

To avoid overheat, I think the air flow should be like this:

enter image description here

Is there any case designed like this? (I want a mid tower or full tower rather than mini towers)

Thanks in advance.

bobo

Posted 2011-03-25T17:50:25.963

Reputation: 1 649

Question was closed 2011-03-25T23:23:30.547

Answers

13

Not the answer you're going to like:

Most computer cases are built to both maximize airflow and direct the heat transfer away from the intakes. Pulling cool air in from the front and side then blowing hot air out the back has been fairly standard for decades. The problem with pulling cool air and blowing out hot air from the same side (the front) is that it will end up short cycling and just pulling in the hot air being blown out.

Hyppy

Posted 2011-03-25T17:50:25.963

Reputation: 3 636

1+1 Major players like IBM, HP, Dell, etc have spent a fair bit of money and research on this. You really need cool one side and hot the other – Dave M – 2011-03-25T18:02:28.423

1Well, the air intake could be at the back, so it should work. Not sure if I want to have hot air blowing on me though. – Xavierjazz – 2011-03-25T18:09:12.947

1That's the other reason they aren't on the front. The hot air would be blasting out toward the user. – BBlake – 2011-03-25T18:33:20.297

3

Considering that warm and rises, the case layout you are suggesting would lead to the warm getting sucked back into the case again.

The typical case design you see, with the Power Supply up and back, is based around the official, and conventional extensions, of the ATX standard.

Mr Alpha

Posted 2011-03-25T17:50:25.963

Reputation: 6 391

3

  1. Hot air tends to go up, so your blowing air against that direction.

  2. Hot air that goes out can get back in for that same reason.

  3. Air from the back has enough space to escape on the picture you gave,
    add the volume of the space at the sides and the top to get an idea.

Combining these, air that goes in the bottom front and out at the top back is the ideal solution even if you put it inside a closet. An easy test would be to check your idle & stress temperatures in & outside the closet.

Tamara Wijsman

Posted 2011-03-25T17:50:25.963

Reputation: 54 163

2

Most computer chassis put the PSU at the back, because many PSUs have a noisy fan. The system sounds quieter if that fan is as far away as possible from the user, who is usually closer to the front of the chassis.

Also, some users don't like hot air blowing directly on them.

Have you considered:

  • Many cases have a "solid" front, with no air flow through the front panel. Could you turn such a case around, making the solid side the "back", and pressing that solid side against the solid sheet at the back of that desk?
  • Could you use a common case that sends the hot air out the back of the case, and cut one or more vent holes in the back of the desk to let the hot air out. (There's going to be a little gap between the back of the desk and the wall where that hot air can get through, right?)

David Cary

Posted 2011-03-25T17:50:25.963

Reputation: 773

A hole cutting saw (like the kind used to make doorknob holes but a bit larger) would also provide a clean hole but allow much more airflow. If you like you can place a fan grill over the hole. http://en.wikipedia.org/wiki/Hole_saw

– Chris Nava – 2011-03-25T21:53:05.647

1

Have you checked out the back of the desk you intend to buy to see if there are any vent slots? If not, you may be able to drill some or install a vent grille. I have modified a couple of desks like this in my time by carefully drilling a row of 8mm holes in the thin board at the back of the desk about 10mm from the top and bottom of the area where the PC will sit.

Drill the back board before you put it in place (on a work bench, on the floor or a protected table surface). If the back board is thin plywood/fibre board, mark out the drilling positions and put a piece of (unwanted or spare) softwood under where the holes will be - this stops the drill bit from ripping up the material or punching out bigger holes when the drill breaks through. Use a wood drill bit to give a clean cut - HSS/metal drills may not break through cleanly at all.

Linker3000

Posted 2011-03-25T17:50:25.963

Reputation: 25 670

My experience here is that unless the power supply lines up with your vent perfectly or have lots of vent space, you still tend to accumulate a lot of warm air at the back of these spaces that's not good for the system. – Joel Coehoorn – 2011-03-25T22:01:13.797