Weird AC3 probs

[4lex]

Bit of a long one, sorry in advance

I've made an .avi with an AC3 soundtrack using the gordian knot package, and it plays fine.... up to a point.

I've been trying to get AC3 sound to work properly and having no luck. The machine I'm trying to play it on is a shuttle SV24, celeron 533 and 512mb, it plays DVDs fine in 5.1, and doesn't seem to struggle at decoding the AC3 .avi

If I install the multichannel WINDVD audio filter BSPlayer and PowerDIVX (versions dl'ed from here today) both have audio waaay out of sync with the video, but playback under two chanel audio filter is fine. WTF?

I've been puzzling this for a while, just re-formatted the machine, it's a new install of Win2k/SP2, DX8.1, all relevant latest drivers, DivX 5.02 and WinDVD 3.1 full version (for the multichannel audio filter)

Thanks for reading all that - any suggestions very gratefully received !

Alex

[4lex]

Think I've figured it - I'm using a software AC3 decoder and the CPU isn't up to the job. Just tested some regular mp3 encoded avi's which playback using 70-85% of available cpu time, the AC3 one is at 100% all the time.

Will a 800MHz C3 cpu be better than a Celeron 533 ? I have one kicking about somewhere.

Cheers,
Alex

[MaTTeR]

What is a C3? Celeron III or something? If so I think they might be 100FSB, so yes it should be up to the AC3 decoding job. It's not the ideal way but should work.

Your CPU usage still seems pretty high even with the MP3 playback. Oh, just noticed your using Divx 5.x so that explains the high CPU usage most likely:scared:

[Kyo]

The C3 of via have 3dnow and mmx but i really think that it will not help so much, I don't believe that the ac3 decoders have sse mmx or 3d-something optimization, Besides the 133 Mhz FSB of the C3 will help ahead of the 100MHz of the celeron, Just Power Up your C3!

/Escuse the English (only the bad parts ):D

[kilg0r3]

some additional things you could try.

1. use ffdshow to decode your divx5 video. it uses lesss cpu time

2. overclock a little :D

[4lex]

Its a VIA C3 chip, I think this 800's a 100MHz bus (can't remember) but my old celery 533 is on 66, so I'm hoping it will help.

I'm trying to run it in a Shuttle Spacewalker box (shoe box sized pc if anyone hasn't seen em) and cooling is poor at best, so I'm not keen to explore the rather rudimentary overclocking features of the board too much, although it could be a goer on the C3 if it can substantiate its claims of passive cooling being sufficient.

I have all the fans running on 7v to try to keep the noise down, so there's not a huge amount of airflow available and nowhere near enough space for a water system.

I've read though that the multiplier is not permanently locked on these cpus - does anyone know how to change it? I could arugably take it up to maybe 900.

Cheers,
Alex