[mythtvnz] Basic hardware help

[Steve Hodge]

On Sun, Mar 16, 2008 at 3:39 PM, Stephen Worthington <
stephen_agent at jsw.gen.nz> wrote:

> The PCI bus has very limited bandwidth when compared to the bandwidth
> used for video.  That is why AGP and then PCIe were invented.  A PCI
> bus has insufficient bandwidth to handle the video traffic for doing
> very much.


At PAL resolutions you'd probably be ok, at least if your drive controller
is on a separate PCI bus. PCI is 133MB/s and 720x576 at 50Hz works out to about
80MB/s. Of course if you're also trying to record from 2 tuner cards on the
same bus you might have problems.


> AGP is *much* better, especially AGP 2X and AGP 4X.  Your
> hardware old enough that it is unlikely to support 4X, but if it has


AGP 4X came out in '99 or 2000, I don't think the motherboard is quite that
old.


> an AGP slot, you really need to use an AGP card, not a PCI one.  There
> should be cheap ones available on TradeMe.  Watch out for the voltage
> specs - AGP is 5V, and I think AGP 4X is only 3.3V, which older PCs do
> not support.
>

You'll have to be careful as it's been awhile since 3.3V AGP cards were
common. I think most nVidia FX5200's support it, but newer cards will
probably only support 1.5V AGP.

Cheers,
Steve
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.ourshack.com/pipermail/mythtvnz/attachments/20080316/c200acd2/attachment.htm