I wanted to build a system which is better than the PS3 slim - smaller, faster, quieter and more energy efficient. I succeeded only partially, but I will try again with Kaveri and in the mean time I'm happy with my little gaming machine.
Comparing the size you can see that my system is smaller - despite the huge power brick.
I wanted a system I could use for playing at 720p with medium to high details, so I went with AMD's trinity APU. A low power intel processor like the i7-3770T combined with a Radeon 7750 would have given me more performance at about 100W TDP, but small cases with support for an half-height expansion card were difficult to source in my part of the world and I had thermal concerns.The configuration
AMD A10-5700 (65W Trinity, 3.4GHz, 4 GHz Turbo)
MSI FM2-A75IA-E53 (BIOS v1.2)
2x4 GB G.Skill Sniper Memory (1866 MHz 9-10-8-28, 1.5V)
Samsung SSD 830 128GB
PicoPSU 160XT with 192W external brick (89% avg. efficiency)
Noctua NH-L9a CPU cooler
In fact, I ordered the M350 and the PSUs from the US, because it was cheaper than ordering from most European shops. That's also why I got the huge (both physically and in capacity) 192W power brick - it was a cheap option to get a high-efficiency power brick.
Using a high-efficiency power brick paid off, as my measurements
show: 23W idle and <90W while gaming are quite good. In idle this is a bit more than 2.5 times lower than the PS3, but for gaming the PS3 uses less energy.
Heavily inspired by the M350 race machine
I also built a different front and due to size constraints I had to tape the SSD to the underside of the case. To do this I had to put different feet to increase the distance from the floor.
This little system is up for gaming at 720p at medium to high details and loading times are very short thanks to the SSD. I haven't done a visual comparision, but I will count this as a draw for the performance and a clear win for the SSD equipped system regarding loading time.
For noise, a look at the opened case gives a good idea of potential problems:
The RAM blocks one half of the cooler's exhaust and the other half is directed towards the I/O-shield - not a recipe for efficient exhaustion of hot air. Furthermore the hot air will raise and be sucked in again by the cooler. This is actually no problem with an opened case, but with the case closed this leads to the fan running at 100%. (Thermal target in BIOS is 55°C.)
SPCR has reviewed
the intel version of the cooler with the same fan. To my ears it is inaudiable at slightly more than 1000 RPM (the rotational speed at idle), but becomes noticeable at about 1800 RPM, but not badly so. At about 2000 RPM it is still below the noise floor while gaming and has a pleasant sound. At full speed (reported as 2500 RPM) it is loud and distracting.
I tried some things to improve this (reversing the fan, adding fans, turning the case), but in the end I settled for a two zone design:
A cardboard layer separates the cool incoming air from the hot exhausted air. This removes the cooling effect from the upper part of the case, but leads to fan speeds of about 2000 RPM while gaming. I still can get the fan to shortly speed up to 100% while stress testing and I'm afraid in summer I might have some problems with noise.
I wanted to avoid the board cooking in the hot air, so I added a 40mm fan. The noise is OK up to 4000 RPM and clearly audible at 4800 RPM, but not distracting while gaming at a living room distance. With an airflow rating of 8m³/h it is probably not hugely effective at cooling (the 92mm fan of the CPU cooler can do 50m³/h), but some parts close to the fan feel cooler to the touch. Unfortunately I don't get reliable thermal data from the programs I tried, so I have no better data upon which to base my decisions.
Lastly there is coil whine from the PSU at idle. It is worse with C6 activated, but does not disappear when it is disabled. This is no big issue for me, but might be for someone building an HTPC with similar hardware.
Winning against the PS3 on noise is easy - the disc drive has a horrible sound and the fan can be heard in quieter scenes, although not badly so. Neither are silent and in summer this might change, but for now I prefer the noise from my machine to the PS3.
Undervolting is currently not effectively possible (PSCHECK and BIOS do not work. Overdrive does, but installing it disable Wifi and Bluetooth), but there is hope for the quick release of a tool capable of changing voltage