786H v01.13 is a BIOS version for the 8100 Elite, so I am going to assume that is what you have.
If this is the SFF (small form factor) version of the computer, then no.
If this is the larger version, there is still a major problem. The power supply in that computer does not supply enough power for the GTX 660. While you could get a new power supply, it may not fit and the motherboard does not have the standard 20 (or 24) pin connector.
Short answer ... it would be difficult to get that card working in that system.