Update 9/2/2019: I have upgraded the CPU to an i7-9700K which created even more thermal challenges. My latest attempts at squeezing out every degree is at the bottom of the CPU Cooling section below. Some pictures have also been updated and screenshots of thermal tests done with different PC positions (laying on its side as opposed to standing straight up) have been added.
I've had some prior experience building an HTPC, but with this one I had 3 big goals:
- It must be portable
- It must be fast
- It must be cool & quiet
Ultimately, I wanted a "dumb" PC console that I could easily transport, set up, boot right into Steam, and worked out of the box with multiple controllers. The first point worked out well enough, the second was a little difficult, and the third was a major challenge. I think I utilized just about every available inch of this build to maximize airflow.
Man, this case. Silverstone did a great job designing something so low profile, but with some really decent vent placement and airflow considerations. There were some oddities that I had to change to get better performance out of it, but overall I think its a really great design.
Some things I modified:
- There is a 15mm gap between the steel body and the aluminum shell. This is a ton of potentially wasted space, so I was able to route some cables (and extra RGB lighting!) into the outer shell.
- The included PSU outer bracket leaves a lot of extra room if you use an SFX type supply (and why wouldn't you with a build like this?), so I removed it and mounted the PSU directly to the outer shell. It took some cutting to create a few new access holes for the power cord, but I shaved off at least 3-4 inches of extra space for cable routing and increased direct airflow from the vent below it.
I found a decent enough deal on this used card, but I quickly discovered that the heatsink (despite how massive it is) was not that great at all. Doing some research, I found and installed the RAIJINTEK MORPHEUS II cooler. This new heatsink is absolutely fantastic, lowering my original temps of around 80C to now less than 60C at max load in Superposition's 4K Optimized tests.
Unfortunately, this also meant that the cooler itself would now be too big for the included case GPU bracket, along with new cooling challenges. I solved these by fabricating a new steel/copper bracket that wraps around and better supports the heatsink (and looks pretty steampunk!), and utilized the two larger 120mm intake fans directly in front of the GPU by hooking up an adapter that connects both fans directly to the card itself.
Update 9/2/2019: I got a great deal on a lightly used i7-9700K and wanted to see if the excellent performance I was seeing with the H75 would help with an extra two cores. There were immediate issues with the current setup - running a basic test with Prime95, I was seeing sustained temps of over 90C+ on the CPU before I ended the test. It seemed that once the H75 reached thermal saturation of around 88C, the cooler would simply give up and temps would skyrocket.
So I went drastic. I delidded the CPU, removed the indium solder with a very handy kit from RockitCool (no razor blades required!) and to go that extra mile, I replaced the CPU socket with a direct die bracket to completely skip the need for a heat spreader. After some trial and error with the liquid cooler bracket and applying some Conductonaut liquid metal (to both the die and the cooler contact plate, GamerNexus was right about the surface tension of the material), I was ready to see if this all paid off.
And it did! The temps now were a manageable low 40's at idle, with mid to low 80's at max load. I discovered that I could attach a wider 25mm PWM fan to the radiator, so I went with the NF-A12X25 2000RPM fan at first, then tried the NF-F12 3000RPM industrial grade fan. While the NF-F12 did drop temps by about 5C, I found the extra 1000RPM made it just too loud, so I switched it back.
The build definitely runs a bit hotter now with the CPU maxing out around 85C in Prime95. But under more realistic gaming conditions I've found that number is closer to 75-80C max with games like Forza Horizon 4 on Ultra @ 4K.
Original text for the i5-9600K:
Cooling the CPU took me a quite a bit longer to figure out. I tried 2 other cooling solutions in an attempt to maximize airflow in the tight space:
In both cases, I wanted to find a heatsink that would leave just enough clearance for a large fan mounted to the case itself (connecting it to the CPU fan header), potentially maximizing airflow while also reducing the weight of the CPU heatsink - making transport safer. I tried a few different fans in addition to stock ones (in a push configuration) with these heatsinks while putting it under stress with Prime 95:
- SilverStone Technology 140mm PWM: This fan has ridiculous CFM output with its 38mm height. With the Reeven Brontes, there was just enough clearance for both. Unfortunately, the fan is also ridiculously loud. It also created issues with the other fans - it was putting out so much air pressure that it was not only pushing the air back out of the other 120mm Noctuas in a positive pressure config when it went full throttle, but because the case did not have enough vents to exhaust, it was back flowing itself too! The temps were not the best either (81 max in Prime), so I moved on.
- Noctua NF-A14 PWM (with 120mm adapter): the hope was that the larger 140mm size would compensate for the 1500RPM limit, and the reduced CFM would work better with the other fans. Unfortunately, when Prime kicked into high gear the fan could just not keep up with the heat. I killed the test after it reached 86C.
The overall issue seemed to be that because there is literally no room inside the case, too much positive pressure from different competing fans would cause hotspots inside the case and not allow anything to vent out properly.
Enter the Corsair H75. It was a tight fit, but after making significant cable management changes, reconfiguring some case parts and combining it with a 120mm slim Noctua fan, this cooler with a negative pressure configuration has worked incredibly well. It pulls in air from the GPU fans and back vent, pushing hot air directly out of the case. Using this cooler, I was able to achieve my target temp of 70C max.
Various Low-Profile Improvements
I experimented with a few different low profile cable solutions. Some didn't work out that well, but others went a long way to making the build more manageable. The USB header cable for the case was very rigid, so I removed it and hot glued these new flat cable ones to the circuit board. Saved a lot of headache in the long run.
The Silvertsone Tek SATA cable was also a big help in reducing clutter.
Thermal Paste & Pads
I used the Thermal Grizzly paste for the GPU heatsink and the
thermal pad for the CPU. The pad works surprisingly well and with the detachable water block, it makes tearing down a lot easier.
Update 9/2/2019: To squeeze out every degree possible, I've gone instead with Thermal Grizzly's Conductonaut liquid metal TIM with a direct die transfer.
It took a bit of research, but I found a bag company that makes various sized bags for musical equipment. One of these bags happened to fit my PC perfectly. Combined with low-profile drone antennas and custom magnetic IO shield cover, this PC is going places.
Thanks for checking out the build! Hopefully this helps anyone else who makes this case their own. It was a lot of fun exploiting every inch of this system.