I now have spoken to VIA Embedded on Facebook, asking about new drivers that support HD playback on the P820 board and the answed I got was:
VIA Embedded yes, we do but we don’t provide chipset driver directly to end users. If you are our customer, please contact with our sales representatives.
On my other question if I was supposed to buy the driver from them to get it to work I got the answer:
With this information I would never ever have bought the moder board from them. This is also discussed at VIAArena. I really hope sone drivers will be released or else I will have to see how good the P820 blends.
The last couple of weaks I have been testing my VIA Epia P820 and the result so far is not good. My first thought was to run FreeBSD and using the OpenChrome driver but Via do not provide enough information about there boards so the OpenChrome team have not been able to make the driver fully support the VX855 chip. Because the OpenChrome driver did not work I tried the source driver VIA provided witch was using an old library from the X.org project called xf86Resources.h and from what I can see no BSD or Linux distribution is using that lib. Since all distributions did not have that library and did not support it the driver did not even compiled. Then i tried different Linux distributions with the same result. I even compiled X.org from source. And I have found out that almost every one who tries to use Linux with the EPIA-P820 & Amos 3001 fails.
Since VIA also has drivers for Windows I had to try, they work quite good you can watch movies in 480p (in the specifications 1080p should work but they do not). One of the downsides was that Windows took 5min and 4sec to boot, not so good for a media center. There is also a binary driver for Ubuntu 9.04 (current version of Ubuntu is 10.04) that I tried. After a day of work I got it to work and now I can watch DiVX movies with the CPU on 100% (do not forget that the board should support 1080p).
So how can VIA say that the EPIA-P820 & Amos 3001 with the VX855 can play HD movies up to 1080p if the do not have drivers for it? Phoronix.com and X.org calls the open source support that VIA has for a bluff, read the article here and the discussion here.