Playing HDTV clips on ATI cards

[hg]

Anyone know what's the lowest speed Athlon system combined with a cheap(est)
128MB ATI card that can play HDTV video clips? I read to play HDTV clips a
128MB card is a requirement. Must be something to do with double or triple
buffering the HDTV frames. I've also read that for software playback ATI
cards are the best as they have some optimizations for assisting software
HDTV playback. Probably more than Nvidia cards.
Reason why I'm asking is I'm wondering whether I need to upgrade my
motherboard to something a lot better( I have an Abit KT7A which can take up
to 2.5ghz barton apparently but at the moment it's only got a 1.4ghz.)
Then again I might have to switch to a pentium 4 as one of the software HDTV
players I've seen on the net says software playback is only possible with an
ATI card combined with a pentium 4 processor. I know that Athlons are not
totally out of the picture however - my 1.4ghz chip has a fairly decent
effort at playing 720p HDTV video but it is a bit choppy and I'm still using
an old 32Mb GFMX card. How much of a performance increase would adding a
128Mb ATI card give?
So what's the lowest speed processor that's able to playback HDTV video? I
really don't want to upgrade my motherboard until a stable mainboard with
the new bus system is out for a decent period of time.

 

[J.Clarke]

Sounds bogus to me. The only rationale for a P4 is SSE2, and I
doubt
players rely on that. A somewhat overclocked 2500+ barton would work
fine I bet.

FWIW, I'm running a FusionHDTV II with an ATI Radeon 8500DV on a 1.4 GHz
Athlon and it works fine.

Which HDTV player did you have in mind?

 

[rms]

Then again I might have to switch to a pentium 4 as one of the software
HDTV

players I've seen on the net says software playback is only possible with an
ATI card combined with a pentium 4 processor.

Sounds bogus to me. The only rationale for a P4 is SSE2, and I doubt
players rely on that. A somewhat overclocked 2500+ barton would work fine I
bet.

rms

 

[Andy Cunningham]

Was that article written by a hardware manufacturer

To play DVD video smoothly you originally needed a 500 MHz processor (P3
class). With the features in modern graphics cards, that seems to be
reduced - my own Celeron 1.5 GHz/Radeon 9000 only uses about 20-25% CPU
while playing DVDs (suggesting 375MHz should be OK).

The top resolution HDTV picture is about 6x the resolution of DVD, so
assuming it took 6x the effort (very unlikely) that would require a system
50% faster than mine. That leaves high end Athlons and mid-high end P4s as
being perfectly capable.

As for 128MB memory, that's just ridiculous. A frame of HDTV resolution
would be about 8MB so a 64MB card would easily cope. I'd guess a 2.5 GHz
Barton plus an ATi 9000 Pro or better would cope with HDTV perfectly well.