What is the best way to capture PC footage? I'm trying to capture footage from a Desktop PC, I don't want to use FRAPS as the quality isn't good enough for what I need and it adds a load of overhead.

I've tried a BlackMagic H.264 but when I click capture and click it to finish my clip doesn't appear to save (It seems the software is pretty unreliable).

Is there a better solution for this? I'd like to capture 1080p with multichannel audio.

Just to clarify, I am using the HDMI out of a Radeon HD5800 card so I'm looking for a hardware solution.
There are many applications which do this, some free, some not - FRAPS should certainly be able to cope if your CPU/GPU is powerful enough (and in fact this may be the limiting factor for whichever application you choose)

So your question title - "what is the best way" - is easy to answer: use a screen capture application, and ensure you have sufficient power to cope.

In the body of the question it looks like you are asking for recommendations on which application to use. This is not really an answerable question - it will vary depending on your exact needs, but many applications will do just fine, given the prerequisites mentioned above.

update - I have been using WeGame, and it works really well, and is lighter weight than FRAPS.