Re: PCI on AGP

[anthony@minster.cs.york.ac.uk]

At 01:13 15/03/2000 +0900, you wrote:
>Hi Neal,
>
>Because 440BX might be more cost effective than 840 chipset.
>And the expression written in 440BX datasheet is still attracting 
>me.(page 11, 29063301.pdf) 
>
>It states that the AGP interface supports 133Mhz data transfer 
>rates and can be used as a Secondary PCI interface operating at 
>66Mhz/3.3v supporting only a single PCI agent. 
>

I too have been looking into using the AGP port as a fast means
of transferring local memory (on the card) to and from system
memory. With 2x transfer rate, 512MByte/s b/w is 'theoretically'
possible (4x over 1GB!). The problem is managing the GART table.
Fortunately, Linux 2.3 comes with kernel support for this. I don't
know about WindowsNT/2000 - I suspect it'll be more difficult
to code!  The drawback with developing for the AGP slot is it
has limited commercial viability - unless you're developing for
a turn-key solution, i.e. who want's to throw away there sexy 
AGP graphics card!!

Tony.