Idea for passively cooling CPU in a case with a vertical PSU

[mathias]

Here's an idea for cooling a CPU passively with a zalman 7000 or 7700 in a case with the PSU right over to the side of the CPU, and not much space in between.

With a PSU with a bottom fan that is so close to the motherboard that it's up to around 2 cm too close for the zalman to fit, remove the zalman's fan and fold the zalman's fins outword, like this:

Code: Select all

Before:
 _
| |
| |
| |
| |
| |
| \____
 \____ \____
      \____ \____
           \____ \____
                \_____
		
		
After:		
 ___________     
|_________  \
          | |
          | \____
           \____ \____
                \____ \____
                     \____ \____
                          \_____

But I don't have a zalman 7*00, and I haven't worked with this kind of case is a long time, so I don't have too good an idea if this would actually work. And I don't really know what kind of CPU this could cool. So it would be good if someone could give a more informed opinion of how well this could work.

[IsaacKuo]

If I understand your concept correctly, then you have a mistaken idea of how the fins on a Zalman flower cooler are arranged. You seem to be thinking the fins are arranged like petals of a flower forming a bowl, so you can fold the tips outward to flatten/expand the bowl.

The fins on a flower cooler are actually arranged like pages of a book, where the book is spread open and the pages fanned outward. You can't just fold the fins further outward.

[mathias]

I didn't mention a zalman flower, those are the 6000's, 6500's, 3100 and 3000's. I was refering to the newer zalmans with the embedded fans.

[IsaacKuo]

The 7000 and 7700 are also considered "flower" coolers, I thought.

Anyway, I still don't see how you're supposed to fold the fins "outward".

[mathias]

Anyway, I still don't see how you're supposed to fold the fins "outward".

The folds would be at a a line 45 degrees from the edges, and it would look:

Code: Select all

Like this from one side
 ___________     
|___________\
          | |
          | \____
           \____ \____
                \____ \____
                     \____ \____
                          \_____

And like this, except mirrored, from the other:

 ___________     
|_________| \
          | |
          | \____
           \____ \____
                \____ \____
                     \____ \____
                          \_____

Just like if you were to fold a narrow strip of paper to give it a 90 degree turn.

[IsaacKuo]

I'd thought of that, but the fins are really densely packed next to each other. You'd have to bend them a lot just to have the space to fold a fin, and even then that sort of fold seems rather difficult.

Personally, I'd just fashion a simple duct and/or flip the PSU fan.

[mathias]

I haven't had much trouble bending a CNPS3000, including moving the fins around a fin to make room. It's apparenly so easily bent, mine got a bit mangled in shipping. 7700's look to have fins that are more far apart than 7000's, anh 3000's. Problem is, they're not compatible with older CPU's which this would work best with.

Part of the point of this is to be able to use it in a case that doesn't have much room for a heatsink, eg if you have an old case that you'd like to do something with, or if you don't have room for a larger case.

But I do see that this is not a good idea outside a few specific situations.

[euimin]

I'd thought of that, but the fins are really densely packed next to each other. You'd have to bend them a lot just to have the space to fold a fin, and even then that sort of fold seems rather difficult.

Personally, I'd just fashion a simple duct and/or flip the PSU fan.

agree. i am also personally a fan of ducting. let me first tell you that i respect your idea, mathia.

if there was a set up where the CPU socket was right below the PSU's 120mm fan, why not just use a tower style fanless heatsinks? examples include Scythe Ninja and Thermaltake Sonic Tower.

if the socket is not as close to PSU, you can use Evercool Air Duct to connect your CPU heatsink and PSU fan.

EDIT: oh~~~~ vertical PSU. sorry. didnt catch that. ya, thats a VERY GOOD IDEA

[ronrem]

I was thinking recently about a homebuilt case,using the Coolmax CR 400 PSU...which has a 3 speed 140 mm fan. I believe that LOW is about 1000 rpm or a bit less-and yet the thing is so big it can move quite a bit of air. Have that a few inches from one of the big Scythe passives,with a well done duct to feed ambient air to the cpu + chipset areas and a 1-fan rig ought to be real doable,especially for a Venice. A homebuilt can use lots of tricks to isolate HDs while keeping them cool and semi-muffled. Airflow routes can be planned. I think there's stuff that can be done with copper pipes as a passive way to reduce temp difference between air inside and air outside without having a noisepath.