Can my computer play raw HD video?

That sounds like a very very basic computer for HD work - however, nosing on a website this might help you:

Requirements to play FullHD with a standard Codec:

Processor: 2.4Ghz (dual core) or 3.5Ghz (single Core) processor.

Graphics: Nvidia/ATi having bare minimum 256MB Video RAM and core clock 600Mhz.

When you try to play it in a lower config PC, the video plays but is often jerky. That’s like almost every PC can do it. On average, this means even a 4 year old PC can play it.

NB: On graphics and processor. make sure you have something higher than even the basic requirements. Because boarderline specs will only scrape playing HD video. it will be very jerky, laggy, and painfully dreadful to watch.

Good luck now!

First understand that HD video isn't what analog video was many years ago with video tape, bad looking quality and that kind of thing. Because of that HD video generates a very large data stream that many older computers, or smaller ones as well, aren't able to handle. I'd say your computer is to old or small to handle HD. I had exactly the same problem when I upgraded to HD video. I had to upgrade my computer as well. Good luck and may Our Father bless your child.