Alienware Alpha/Steam Machines are really a bigtime value, holy cow.
I have been toying with a build of my own for a little while, and now I am seeing open box Alienwares for $380. That price is hard, and I do mean HARD to replicate.
1) 19v DC external PSU (accomplished with AM1H-ITX).
2) Wireless AC + BT (mini PCIe card fits the bill but for ~20$ extra).
3) 4130T CPU (in my opinion the hardest thing to get performance on-par with).
4) Very low TDP (done).
5) CPU/RAM/Storage upgrade path. (Add in the GPU upgrade path for the hobby build, but why at 4x and paired with a 5350?)
6) Ultra Small form-factor. (SilverStone RVZ02 is pretty slick for this form but still huge compared to the Dell err.. Alienware)
7) Controller bundled! (~$50 add-on).
The build I am (was?) attempting was a AM1 setup that also supports a DC adapter like the little Alienware.
AM1 5350, 750 Ti, ASRock AM1H-ITX mobo (4x PCIe, DC support), 120w Toshiba DC adapter, DDR3 1600mhz, 2.5" drive.
Best case for this setup seemed to be the SilverStone RVZ02 as it is a mini-itx that houses the SFX psu internally so there isn't a big hole where it should be if opting to use DC.
Pros
1) The fun of the build.
2) More robust BIOS features.
3) Room for 2x 2.5 and 1x 3.5 drives. If the case has to be bigger, at least it can be put to good use.
4) Could run with APU reducing the build to HTPC only duty at only 25w TDP(!!!!). Hint: I think this is where I am headed. (Dell 3050 and Acer Revo Build cover this type of service, albeit with almost zero upgrades possible)
Cons
1) AM1 upgrade path stops firmly at the 5350 right now. It is the top AM1 and I doubt we will see the socket used anymore. The 1150 motherboard doesn't offer overclocking but will support a variety of more powerful CPUs should they come down in price.
2) The PCIe port is 16x but electrically only 4x.
3) 5350 is not on the same level of performance of a 4130T. The 4130T is only 10w TDP more (5350 25w, 4130T 35w).
So I think after playing around, it might be time to send the 750 Ti back, and call it good with just using the APU and removing the thought of 3D gaming.
Costs:
Alienware Alpha i3 4130T open-box:
$380
Alienware Steam Machine i3 4130T:
$430
Hobby low-power HTPC
PCPartPicker part list /
Price breakdown by merchant
CPU: AMD 5350 2.05Ghz Quad-Core Processor ($38.99 @ SuperBiiz)
Motherboard: ASRock AM1H-ITX Mini ITX AM1 Motherboard ($48.99 @ Micro Center)
Memory: Kingston Savage 8GB (1 x 8GB) DDR3-1600 Memory ($30.99 @ Newegg)
Storage: Toshiba 500GB 2.5" 5400RPM Internal Hard Drive ($37.50 @ Other World Computing)
Video Card: EVGA GeForce GTX 750 Ti 2GB Video Card ($109.99 @ Newegg)
Case: Silverstone RVZ02B HTPC Case ($64.99 @ Amazon)
Wireless Network Adapter: Intel 7260 802.11a/b/g/n/ac Mini-PCI-Express Wi-Fi Adapter ($24.98 @ OutletPC)
Total: $356.43
Prices include shipping, taxes, and discounts when available
+
Power Supply: ($11.38 @ Amazon)
+
360 Wireless Controller + Adapter for Windows ($50)
-or-
+
Steam Controller ($50)
$417.81