At 23:49 -0700 09/24/2002, Kevin Diggs wrote:
>Hi,
>
>     Has anybody ever seen the back of an 8600 motherboard? Is there an
>ATI mach 32/64 video chip? I would remove mine but am sure I would
>somehow blow it up.
>
>                     kevin


Yes.  No.  The video on the 8500 and 8600 is supported by custom 
Apple chips which are not on the PCI bus.  The video for the 
7500/8500 class machines is on it's own bus separate from the PCI and 
uses it's own bridge between the CPU/memory bus and the video bus. 
The bridge is called CHAOS.

On the back of the 8600 you'll find the ROMs (341S0280 - 341S0283 or 
341S0380 - 341S383), the pair of Data Path controllers (343S1141), 
Hammerhead (343S1190), Bandit (343S0020), Grand Central (343S1125), 
Curio (Enet, SCSI, serial) (AM79C950), and then most of the video 
chips (343S1154, 343S1155, Phillips AC7150.1 and BT9055, the RAMDAC). 
343S1138 is on the front of the board.   I'm not sure which of those 
is actually the video bridge though.  Anyone know?

Jeff Walther