Plase, Please, don't look to me for any expetise. Actually, BaldEagl pointed out this issue but I think he may be in the steep phase of the learnig curve just like us.
Here is an excerpt from a Tom’s hardware review of the 8800GT that convinced me that the PCI-e 2.0 vs 1.0 (or is it 1.1?) will make no difference to me.
“Finally, the GeForce 8800GT introduces PCI Express 2.0 support, which will double the bandwidth (moving up to a bi-directional 8 GB/s) with an X38 motherboard. This won't change anything from a gaming point of view, but could be more interesting for workstations, professional software or applications using Nvidia's GPGPU CUDA. It remains, of course, fully compatible with PCI Express 1.0.”