Question : Problem: What are the motherboard compatability issues between PCIE 1.0 x16  and  PCIE 2.0 x16

HI,
I would like to replace my Gigabyte Nvidia 6600 PCIE 1.0 x16 which has DVI and Analog connectors with a similar compatable card with two DVI connectors.  I use my system for Photographic editing and it is calabrated for CMS.  I do not use my system for advanced graphic games.  Though, I would not like to lose this option if possible.

I contacted Gigabyte and I have included the conversation with them below.   What are they talking about and is an equivalent graphics card still available that will be compatable with my motherboard?

My question to Gigabyte:

"I currently own a GA81945-P motherboard.   I have a GV-NX66256dp graphics accelerator installed. My analogue monitor failed and I'm replacing it with a second Viewsonic LCD monitor. My first Viewsonic is a VX2245wm LCD Display.
Im purchasing a Viewsonic VP2250wb LCD Display to replace my analogue monitor. The GV-NX66 has one dvi port and one analogue port. I need to replace the graphics accelerator with an equivalent or better Nvidia accelerator with two DVI-i ports."

Gigabyte's Answer:
"hello,
8I945P onboard PCIE slot is PCIE 1.0 x16 most current dual DVI is PCIE 2.0 x16 that may not be fully work on this board suggest get any PCIE1.0 x16 even card only has one DVI one analogue using a adaptor convert to analogue to IVD-i match the monitor connector will be better to run ."

Unfortunately the Gigabyte Nvidia GV-NX66256dp does not look exceptable  when connected to  the analog connector.
Thanks for your help,
Howie

Answer : Problem: What are the motherboard compatability issues between PCIE 1.0 x16  and  PCIE 2.0 x16

Better to indicate a problem may exist on old hardware :-)
This way no backward compability issues, complaints. :-)
Go to ebay and buy your PCIe v1.x. Graphic card there. It is best choice for your
graphic needs, and for the fraction of the price. Good luck!