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Homemade watercooling system for PC

Many different water cooling systems for PC exists,
but they are expensive if you go all the way...
So I decided to construct my own.. super cheap..
You need access to different machines to make this possible,
fortunately my company has great stuff like that..

The main reason I am constructing this water cooling system,
is that I sleep near my PC, and I need the possibility to make it download while I sleep..
With air cooling (using fans) it is not possible to fall asleep :-) even after all my air cooling improvements..

Here is the main problem: a CPU using 65 Watts of heat power that needs to be cooled down to under 50 Celcius.
If this is done with air as you see on the picture, you need a big heat sink and a big fan running at least 3200 RPM.
Note the series resistor I have added to the red wire, it's 56 Ohm and changes the fan speed from 4900 to 3200 RPM.
This increased of course the CPU temperature from 45 to 51 C, still under the max critical point.
I dont need a super cold CPU, but I need a total noise free PC !!

There are 3 other noise generating items, PSU, GFX, HD, I will deal with them later

Copper materials

Here is the copper block I got from my local junk yard for 3 $
It measures 160 x 80 x 10 mm and weighs over 1 Kg.

Here are the copper parts cut out and ready for the milling machine.

CPU Waterblock

I have removed the CPU heatsink and WOW I found out my motherboard have 4 mounting holes for big and heavy heatsinks.
So I carefully measured it all down to the last detail, here it is:

The blue lines are the CPU and CHIP size. Red is copper outline with a center line drawn, (all milimeters)

Here are two ways to mill the water tracks in the CPU water block.
Idea A: gives the lowest waterloading = higher flow, and the same cold water cool down the whole CPU area.
Idea B: gives longer watertrack = higher output temperature, more water loading, hotter CPU.
Idea A is also much more easy to make, the idea to construct water tracks in parallel comes from car radiators and coolers.

First I hand drew the milling tracks, then I wrote all cordinates down.
Then It was easy to turn all the handles to reach each cordinates, but the time it took was huge !!
The top plate is 2mm thick and the brass water connections are 9mm like all my other water blocks.

After soldering and sanding, it is time for the 7bar air pressure test. The bottom side edge has a small cut, for the socket.

As usual I painted it black mate. The rear side is polished using 400 -> 600 -> 800 -> 1000 grain sandpaper.
The core and bus voltage regulators have been modified with a heat spreader, to keep temperatures down.

I am extreamly satisfied with the complete system, now it is silent, wow..
See CPU test results

Chipset Waterblock

Here is my water block for the chip set on the motherboard. It measures 35 x 35 x 10 mm, +2 mm top lit, the water track is 8 x 8 mm
Note the details so the brass hose connections fit perfectly into the copper lid,
this cut helps a lot to hold everything in place when soldering. Pic

After soldering and sanding, it looks really nice :-) Pic - Pic
I painted it black mate, to make it possible to measure the temperatures later
with an IR (Infra Red) temperature meter.
Click HERE to see this block mounted on my motherboard with LM50 sensor.

GFX Card

Here is my water block for my GeForce 2 GFX card. The water connection is side mounted,
this way it is best to connect water hoses to it and keep it nice and simple.
The water connections were drilled at 7.8mm exactly, See a perfect fit
Here is another closeup picture of the inside water connections
After soldering I milled the top plate and sanded it. I am happy about the soldering results
This block is 35 x 35 x 10 mm + 2 mm for the top lit. To finish it nicely, I painted the top and sides black mate.

Original GF2 - Removing Original Heatsink - Cleaning nVIDA GF2 Chip - Gluing homemade waterblock
See test results


Here is the drawing I made when I got the idea for this design.
A copper plate 50 x 145mm that is 2mm thick is used to mount on the sides of two harddisks.
On this plate, 3 small copper tubes are soldered, in the two front ends I will solder
brass hose connections.

It was easy to cut the tubes in a 45 degree angle, here is my test to see if all fits.

Soldering was easy and fast to do, using a huge 200 W soldering iron. Fittings closeup

When it was done, I painted it black just like all the other parts I made.
A copper plate is mounted the other sides of the two harddisks. See test results


- -
Click on pictures for closeups. Now when the drives are watercooled,
it is possible to reduce the sound level and still keep a low opperating temperature.
From about 30 cm distance with open case it is impossible to hear the drives in action,
both drives are max 1 degree higher than watertemperature.
Remember that life time for all electronic parts are doubled when temperature is lowered 6 degree !!
and if you lower temperature 12 degree, life time will be four times longer !

Water fittings and PVC hose

The plastic PVC hose I use is 8 mm inside and 10 mm outside in diameter.
The brass hose connections are 9 mm, they needed to be cut in halves to be used for one waterblock

Water Pump and water flow

Here is my Eheim 1046 water pump, I have of course tested it's performance in my kitchen sink.
Unloaded it perform = 5 Liter / minute
Loaded with 3 m 6 mm hose = 1.6 L / min.
Loaded with 3 m 7 mm hose = 2.3 L / min.
Loaded with 2 m 7 mm hose = 2.6 L / min.
Loaded with 2.5 m 7 mm hose and Chipset cooler = 2.2 L / min.PIC
Loaded with 3 m 9 mm hose = 3.5 L / min.
Loaded with 1.4 m 16 mm hose and my radiator = 4.3 L / min.PIC
This means I get best performance with bigger hose inner diameter, and/or shorter hose length.

Hose inside diameter conversion chart:
1/4"  = 0.25" = 6.3mm
5/16" = 0.31  = 8.0mm
3/8"  = 0.37" = 9.5mm
1/2"  = 0.5"  = 12.7mm
3/4"  = 0.75" = 19.0mm
5/8"  = 0.63" = 16.0mm

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