Personally, I would keep that card around regardless just as a spare, especially since it isn't worth very much for resale. You never know when it might come in handy. I have a 9600Pro and 9800Pro in static bags just in case anything happens to any of the AGP rigs my family has running.
Yep, I've found a use for my AIW Radeon 8500 128. I'll use it in a dedicated PC used just to transfer old anime VHS for DVD archiving. When I get the X1950 Pro AGP to replace my AIW Radeon 9800 Pro, that will go into a PC for my six year old.
I'll be curious to see how Havoc physics on ATI's RD600 board by DFI will check out. Anandtech's review said that the third PCIe x16 was only for physics, they could not use it for Crossfire.
Here's their comments:
The third x16 slot is designed for the upcoming ATI/AMD physics capability. This slot can be jumpered for PCI Express card operation and we are testing it currently. Unfortunately, at this time it appears the secondary x16 slot can only be used for graphics.
http://www.anandtech.com/mb/showdoc.aspx?i=2891&p=2
If a slot is dedicated for the ATI physics, does it even have to be Crossfire, even on a Crossfire board? One would think that a single X1900XTX could be used for graphics and an X1600 Pro for physics.
I also remember a mention in a Twitch Guru column that integrated ATI graphics would be used for physics as well, and not just for an extra monitor. That would make getting an RS690 board a good choice for those not planning Crossfire. The AMD 690 T boards arriving with dedicated slots for the integrated x1250 video memory look good for that.
Of course, it's all a matter for Catalyst to make use of Havok physics, which hasn't happened yet.