Define "crappy". Is it slow to open, or jerky to navigate, or are the meshes degrading to bounding boxes?
There's always a compression delay when a 3D scene opens, and as Acrobat is a 32-bit application none of your extra cores, RAM, etc. have any bearing on the matter.
By "crappy" I mean I get about 10 frames (or less) when trying to turn around my model. Zooming actions are performing a bit better. Having the reduction-options set to bounding-box below 15 frames doesn't really improve performance in navigation, though meshes are displayed as bounding boxes when I try to navigate. Though Reader isn't that much dependant upon ram and processor-configuration, I pointed that out to emphasize that it's actually not a problem of hardware-performance. The real question is: why is there a problem with the new PC that isn't there with the old one?
Could it be a problem with the graphics-card or directX 11?
At least we have managed to narrow it down. It is infact a problem of the afore mentioned ATI X1300 - graphics-card. The Problem is independent of any other hardware and the operating-system.
To confirm this we took out our screwdrivers and swapped the graphics-cards.
We moved the card from the new PC (which was running Windows 7 Professional 64-bit) to the old PC (which runs on Windows XP Professional 32-bit). As mentioned before, the old PC was able to run the file smoothly with its old graphics-card. With the new one it couldn't.
On the other side the new PC can now run the file smoothly with the old graphics-card.
So the performance-problems could be due to either
1) the newest version of the ATI-Catalyst-Driver that was used or
2) the card istself that doesn't fully support the DirectX-features required for Acrobat-3D-annotations to run smoothly. (though it claims to fully support DirectX)