TM7720G: Avivo features not working

Hello, new Acer owner here...

I bought the TM7720G with an ATI HD 2600, mainly because of it's fair balance of gaming performance (I'm not into the latest generation of games anyway) and good media functions (Avivo Video Transcoder and DXVA accelleration, mainly). I'm running Win XP Pro as I have several peripherals that won't work at all or won't work correctly under Vista and whose drivers won't be updated for it. The install is perfectly clean (made only yesterday), a slipstreamed SP2 install on which I've installed all recommended Windows Updates and used only Acer's approved drivers.

However, the Catalyst drivers offered by Acer are incredibly dumbed down, the advanced view isn't available and the Avivo Codecs aren't included. The latest version available on the Acer support site is 8.402 (roughly equivalent of Catalyst 7.8 which uses 8.401 drivers) so I downloaded the matching Avivo pack. However, PowerDVD (which was included with this computer) will tell me that I have DirectX VA but it is not used. Checking the Avivo box in PowerDVD and playing a DVD will result in the box being unchecked for the duration of play, and DXVA will again show that it's not being used.

The Avivo Video Converter will not show in the Catalyst Control Center included with Acer's drivers, it will only show if installing the full equivalent Control Center but I'm not sure that's such a good idea. At any rate it doesn't help with the following problem...

Worse still is the fact that MPEG-4 decoding (DivX, Xvid and such) is horribly broken, showing macroblock corruption as demonstrated in the attached screen capture, these will remain for a few seconds in a static scene and then clear up in non-moving parts of the image but if the entire image is moving the macroblock errors are worsened until the scene changes into a more static one. I was hoping to achieve fast and effortless conversion of my set-top box backups into Xvid format and also the other way 'round, but testing a transcode from DivX to MPEG-2 shows that the macroblock errors are being propagated in the encoded file as well, it's not simply a display issue but an error in the on-GPU decoding process which both the Avivo codecs and the Video Converter uses. The video I'm using to test this plays perfectly fine in VLC or using the real Xvid codec, and MPEG-2 plays fine but won't use DXVA as it should in PowerDVD.

Please advise on the above issues if you can. It's much appreciated, as I can't find relevant information on this problem anywhere on the 'net (just others posting the same problem (on ordinary non-Mobility HD2600 cards, even), but not getting answers).

I'm also running the latest Acer TM7720G BIOS (1.21) that removes SERR# on the Radeon, but it doesn't seem to have had any impact on the problem at hand.

 

UPDATE:
It turns out Acer's PowerDVD build doesn't use DXVA for DVDs by default, it has to be forced through a registry edit. So now I have DXVA active for both DVDs and other Avivo-supported formats.

However, DivX files are still having severe problems as displayed above. MPEG-2 does not have this problem.

And it gets even stranger: doing an Avivo transcode from MPEG-2 to MPEG-4 will result in a file that is perfectly playable, without any of the macroblock corruption as shown above. Avivo seems to use DivX 4.0, by the way.

Note: I have no other MPEG-4 codecs installed so it is handled by Avivo for sure. There's just something in a "regular" MPEG-4 (they were encoded using DivX 5.1.1) that the Avivo codecs don't like, but I can't figure out what exactly. Just by comparing the two files I can tell that it's not any of the usual culprits like QPEL, GMC or Packed Bitstream, because those techniques are used in neither the working example nor in the non-working one.

Any help would be much appreciated.