I want to build a media server...

[NCLI]

I need it to be able to transcode 1080p on-the-fly, as cheaply and reliably as possible. Any reccomendations?

[PurposeOfReason]

Depends what frontend you use. Some decode with the GPU, others the CPU.

Best bet is get some mAtx board, throw in the cheapest dual/quad core you can. Get a good quiet heatsink. Make sure the board has some good integrated video, and about 2GB ram. You're set.

EDIT - Wait, you want a server that streams to a different box that plays the videos? CPU power is all that matters then. 2.5Ghz or higher dual core will be fine.

[gn2]

For a front-end what about an Acer Revo (http://www.reghardware.co.uk/2009/04/24/acer_revo_storage_switch/)?

All you need is a NAS to hold the file and the Revo can play it over the network.

[LowSky]

integraded video for 1080P...no, absolutely not... Nvidia and ATI make some great low end GPU cards that are fanless, and can handle much higher requirement than intergrated graphics.

As for a processor get a dual core or better

[NCLI]

I'm planning to use my PS3 as a frontend, that's why I need it to transcode 1080P to a compatible format.

[gn2]

Why not just use the PS3 as the back-end and get a Revo for the front-end.
That could work out cheaper than doing it the other way round.

[NCLI]

How can I use my PS3 as the backend? I don't think it's possible to share/stream any media from it :confused:

[gn2]

You can rip Blu-ray with a PS3 if you install Linux on it, then you should be able to access the ripped files if they are shared.

A PS3 with Linux installed is just like a PC.

[PurposeOfReason]

integraded video for 1080P...no, absolutely not... Nvidia and ATI make some great low end GPU cards that are fanless, and can handle much higher requirement than intergrated graphics.

As for a processor get a dual core or better
I'm only using some integrated nvidia 7100 right now. Not that I would know, after building 4 media boxes.