One of the the things I wanted to do with my CNC once I got it was to make some case mods to my computer. There were three main mods I wanted to do to my computer. The first one I did was to move the location of the input panel from the side of my case to the front for convenience. The second one is a pretty common case mod: a window on my case door. The final one is the most complex of the mods I will perform. This one involves adding liquid cooling to my graphics card by repurposing a closed loop CPU cooler and using a custom made bracket.
Quick Tech Specs for my computer:
i7 4770k @4.4 GHz
Corsair H100i CPU water cooler with 2 Noctua fans in pull configuration.
EVGA GTX 770 GPU with ACX cooler
16GB 1666MHz RAM
2 TB storage @5900 RPM
2 TB storage @7200 RPM
3x 246 GB solid state drives
600 W corsair power supply
Windows 7 Professional Bit Fenix Prodigy M MATX case
Front power button and USB ports
The first part of this project that I tackled was the front input panel. My computer case, the prodigy M, normally has the power buttons and USB ports on the side of the case. The problem I had with this was whenever I needed to open the case to work on something, I would need to unplug all of the associated connectors to free the case door completely. Also, it was inconvenient at times to access the USB ports. I got the original idea for this a long long time ago while I was swapping out fans in my case. I noticed that the circuit board with for the front IO was roughly the same size as the DVD drive cover plate.
I don’t have a DVD drive in my computer because the CPU water cooler radiator that I have is installed in the top of my case where the DVD drive would need to be too. This made the decision to put my IO panel there even easier. The other nice thing about putting this IO panel in the front of my computer is that I can now anchor down the cables that are used to connect it to the motherboard. Previously, when it was on the case door, I had to leave slack in these cables and then just shove them in when I shut the case door. An interesting complication arose while working on the design for this project: The component I needed to measure was within the computer that I do my design work on. What I did was detach the circuit board and then measure the cutouts that were on the case door. I tried scanning and taking photographs of these parts to make the designing easier, but it did not really help all that much in the end, I used calipers to measure it instead. After making all the edge to edge measurements with calipers, I converted every measurement to center to center of each cutout. This way, I had the true position of each feature, and could add or subtract to the size of each cutout to make it fit the component closer.
I decided to make this out of two parts that would be assembled together. The circuit board underneath has 3 holes for mounting it. The are not symmetrically spaced and I did not think they would look good sticking out the front of my case. The interior section is wider and has a stepped down area to allow it to fit behind the front casing but still be mountable to the case body. The two slots on each side allow for up and down adjustment of the whole thing. The cutouts on this section are over sized slightly to allow this section to slip over all the components allow the correct depth. The outer section has a hole in each corner to allow it to be mounted to the interior section. There are also pockets for the bolt heads of the bolts that attach the circuit board to the interior section. The power and reset buttons have a large plastic housing that goes very close to the surface, and as the inner section has a large rectangular cutout, the outer section has a very deep pocket to keep the buttons almost flush to the surface. For both sections I cut them out of 3mm Black Acrylic using a 1/16″ flat square end mill. Using the smaller diameter bit meant I could make smaller dog bone cutouts at each corner.
My first attempt to cut this out had one small mistake. The inner section first was what I cut first and all the spacing was correct, but I failed to account of the fact that it had to slide over each component completely. The audio jacks are circular are at the surface, but rectangular lower down. I was able to get the general fit up from this first draft, and then get it correct on the second try. During the second attempt, I cut out both the inner and outer pieces at the same time because I was confident in the spacing this time.
These new parts came out exactly like I wanted. The interior section fit completely over each component and the exterior section fit each component even closer. The pocket for the power buttons in the exterior section was extremely thin. This was the desired result, but I did not expect it would make the plastic sort of opaque in this area. Luckily the housing for the buttons is black, so it only looks slightly brighter than the rest.
I used M3 bolts to install everything. Three bolts were installed in the interior section and then tightened into place with nuts on the interior side to make them become mounting studs for the circuit board. Instead of trying to find the right size stand offs, I used nuts on both sides of the circuit board to give the correct spacing. Some shorter bolts were used to attach the exterior to the interior. I used M4 bolts in the slots on each side to install the whole thing into my case. There were already holes in the case around the DVD drive area, and these were re-used to mount my panel.
The only problem I had with the fit was the reset button. The placement was wrong by about a 1/16th of an inch. Rather than waste another section to re cut the exterior section, I just filed down the edge slightly. The bolt heads that are visible might also be restricting the front panel of the case from snapping into place completely, so a redesign of that may happen later to give better clearance. Overall though, I am very pleased with the effect.
The next part I worked on was a case window. I had always wanted to make my own case window and now that I had a CNC I could cut out any pattern that I could come think of. My case was also lacking in the air flow department, so I also cut in mounting and vent holes for a 230mm fan. I looked around online for a long time, but I could not find the dimensions necessary for the mounting holes of the 230mm fan. Thus, here is an image with the dimensions for the mounting holes. I measured these dimensions off the front of the prodigy case, and can confirm that they fit the bit fenix 230mm spectre fans.
Once I had the mounting hole dimensions and the circular cut out dimensions, I could design a fan grille. The pattern I chose is shown above in the fan dimension picture. I went with an aperture science-ish design. I used smaller shapes and more of them to accomplish the same look as the aperture logo. The smaller, more numerous holes keep airflow high, but avoid large holes where something could get into my computer. I used the same number of cutouts, but going in the opposite direction as it went closer to the center of the pattern.
I used 1/4″ Clear Acrylic from McMaster and a 1/8″ Ball nose end mill. I really dislike machining 1/4″ acrylic because it takes FOREVER. I’m not certain if its because I have my speeds set poorly or if my step down is too little, or just the fact that its a dremel for my spindle (it’s probably this one). It took about 2 hours for it to cut the fan grille.
I mounted the fan with four #6 x 2 inch long bolts and matching nuts. My original idea was to use 1/8″ diameter neodymium magnets to hold the window to the case without using the old case door at all. I milled in the row of pockets you can see above to glue them in, but I scrapped this idea pretty quickly and opted to use some adhesive backed magnet strips instead.
The adhesive backed magnet solution showed itself to not work quite quickly as well. While the one on the left in the picture above fit quite nicely and flat to the case, the one on the right did not. Additionally, the magnets were not quire strong enough to get a good hold and the result that was the window fell off if the case was jostled even a little bit. A new idea for mounting was required. I decided to use the case door that I was replacing and make a cutout for the window in the middle instead. This way the existing mounting method of the door was re-used and the window could be held to securely to the case.
I had to change a couple things to do it this way. First off, I cut my acrylic panel with the intention of completely replacing the door, so it was the same size as the metal panel. This was pretty easy to remedy though, all I had to do was trim the acrylic panel on the band saw. This also allowed me to cut off the old magnet pockets which were not being used any longer.
Now the next part was a little messy. I had to cut out this center section with a jig saw. My dad helped me out on this part and I’m certain I would have done as good a job without him. The messy part was that the jig saw we used had a very dull blade and it had a tendency to deflect backwards while it cut. The metal panel vibrated A LOT while we did the cut. The curves were particularly difficult, but we got it done. Some grinding with a rotary tool cleaned up the edges and once I went over the raw metal with a black permanent marker, it looked like it belonged.
The window was cut such that it was a tight press on the back side of the door. The runners on the backside were large enough for the panel to slide around after it got pressed into place. After I got it in place, I drilled holes through the window and the case and then used M3 screws to secure it completely.
I also used some strips of cork shoved into the channels on each side to ensure that the window was tight and place and to dampen any vibration that might occur. Not pictured, but also required was grinding off the edges of the window corners that interfered with the closing of the door. I only considered fitting the window into the door at first and realized this part interfered also when I tried to install it onto my computer case.
I ended up using 8 screws to hold the window in place. One in each corner and one in the middle of each side was sufficient to hold it together and prevent the window from separating from the metal. I had a bunch of 14mm long M3 Stainless steel screws for other projects, and used them here as well. I think they look very sharp. If I was ordering screws specifically for this, I would probably order pan head screws, but since I had socket head available, it served my purposes.
I’m very happy with how it turned out. The fan does take up almost all of the window, but I needed the airflow too. While I was installing things in the case, I routed my cables a little better, and used orange cable wrap on the cables. It still looks like a mess in there because of all the unused power supply cables, so I may upgrade to a modular supply soon. That way I could plug in only what I use. I think I will also move the solid state drive that I have installed vertically in the bottom of my case to make it look more aesthetically pleasing. A final touch would be some orange LED strips around the perimeter of the window to get a nice edge glow. The Bit Fenix fan has a header that allows for control of the LED’s already in the fan, and my GTX 770 just so happens to have headers for LED control as well. In conjunction with my mod below, I may be able to control the LED’s on my fan through my graphics card. It is intended to be used for on-card LEDs, but as mine uses the ACX cooler, it does not have LED’s.
GPU Water cooling
The last PC mod that I did/am working on is adding water cooling to my graphics card. The idea here is to increase the amount of potential heat transfer such that your GPU runs cooler, or at the same previous temperature, but at a higher clock speed. Rather than building a custom H2O loop in my computer, I opted to perform “The Mod“. This method involves using a closed loop water cooler that is typically used for CPUs. To do so, you remove the stock heat sink from the GPU and then attach the liquid cooler to the graphics card GPU, which is similarly sized to a cpu. The main hurdle in this process is attaching the cold plate from the cooler to the GPU securely. Plenty of the people who have performed the mod have simply used zip ties to hold the cold plate in place. I actually tried to do this with the zip tie method a LONG time ago. In the end I couldn’t get it to hold a stable temperature and my GPU always overheated, causing the system to crash. Below are some of the pictures I took while attempting that.
The CPU water cooler I am using is actually one that comes with an AMD FX CPU, but my friend I bought it from was not using it, so I hijacked it. The ‘FX’ logo on the cover is an RGB LED that is controllable and I am considering adding something other than the “FX” text on top, since it does not make sense on my Nvidia Graphics card.
As I mentioned above, I was unsuccessful using the zip tie method of holding the cooler down. I wasn’t very confident in the method to begin with, but I wanted to at least do a proof of concept. Also, this was attempted before I had my mill. Once I did have my mill though, I decided to give this another go. I measured the pattern of tabs on the cold plate and drew up a design in SolidWorks to fit the tabs. The way it works is that you place the bracket onto the cold plate, and rotate it until it drops between the tabs. Then you rotate it back such that it holds the tabs down. Using screws in the slots, it tightens down and holds the cold plate to the GPU.
***UPDATE 9/24/14*** I now have the hole spacing on my GTX 770! Here it is:
This was cut with a 1/8″ end mill, so the corner reliefs are quite large. I’ve since gotten a 1/16″ end mill and I imagine it would look much nicer if I redid it with that. Also included in this bracket are mounting holes spaced for a 92mm fan if I wished to install one. This fan would blow onto the VRAM modules on the graphics card, but in my case, the fans from my CPU radiator will do that anyways. Searching for my graphics card mounting hole dimensions also did not turn up much. Unfortunately this time I forgot to record the hole spacing of my card. What I do know is that the holes are 3mm in diameter and that the slots I cut into my bracket are between 2.2″ and 2.6″ center to center. I’ll update this part later when I measure it again.
I tried the cut in 6mm Acrylic as well to get better stiffness. The increase in thickness definitely gives better rigidity, but it is too thick to perform how the bracket is supposed to. The thickness of it causes it to interfere with the tubes coming in and out of the cold plate, so I had to sand down a section of it to clear these tubes. I am unsure yet if I will use the 3mm black bracket or the 6mm clear one.
The test fit showed that the bracket fits great. the Tab widths and the cutout diameter are both spot on. I actually have not gotten around to installing this in my computer. I intended to add my case window and side intake fan before I attempted this again. Well, now my case window and intake fan are done, I just need to get to work on this. I am planning on using #4 screws that are 1.5″ long to secure the bracket to my graphics card. Seeing as the screws are metal and might conduct something, I purchased some nylon washers to make sure nothing shorts out. I will update this space with results once I finish this mod!
***UPDATE 9/24/14*** Well I have finished this project and had to revert since then. I was able to get the water cooler to work and cool my graphics card for about 2 months. My idle temperatures were about 7 deg C WARMER than with my default air cooler, but I was able to overclock my GPU to it’s highest setting (per the included software) and be very stable. I am not able to do this with my air cooler. The failure occurred a couple of days ago and just randomly happened when I was trying to run SolidWorks. It appears that the water cooling unit just stopped running, meaning the fluid was not circulating. I was never able to get the correct software installed for the cooler, so I could also be wrong here. Considering the idle temps were actually worse, I have decided to stick with my air cooler for now. Luckily nothing was too far modified to be unable to revert.