Syber's "Steam Machine X" is the only one which meets (or rather, exceeds) the Oculus Rift recommended specs. The critical component is the GPU, and Oculus recommends a GTX 970. This one has a 980.

At $1419 it's quite fairly priced for the components it includes (just check logicalincrements.com), but I wouldn't really call that cheap.

yeah that's pretty pricy. I didn't look very closely at the prices. The low end ones are basically laptops!

I still wish there was a generic off-the-shelf computer that everyone agreed was best for VR. I'm not a gamer and don't have the time or interest to build something just for Oculus. I'd be willing to pay a little bit extra to have the comfort of knowing other people will be troubleshooting the same problems I'm having on the same hardware.

PS4 and Morpheus (when it comes out).

The Syber machines are configurable, though, so you can grab the midrange one and upgrade it to a 970 for a few hundred dollars.

They look like they only take half-height cards - apparently they do sell half-height 970s but you'll have a better selection of cards with a larger case.

It's a bit early to say whether these are compatible with the Oculus Rift, but it's a near certainty that they will be compatible with the HTC Vive, given Valve's involvement there.

Easy, maybe. Cheap, no. You're paying for the brand, the flashy case and parts that fit a smaller form factor (the Alienware machines are using laptop GPUs instead of desktop ones, I am not sure they would support Oculus at all). Cheaper just to assemble it or buy a gaming PC that isn't constrained to the HTPC form-factor.

Not to mention the streaming device gives you the option to run the actual PC in another room, where the noise won't be so much of an issue.

I don't think any of these meet the minimum Oculus specs. You need a GTX 970 which costs like 75% of the entry model

I'm in the exact same situation and completely agree.