i am also experiencing problems with Lock On FC under Vista. I bought myself a new PC:
Intel Core2Quad Q9300
Sapphire ATi Radeon HD 4850 512MB PCIe
4096 MB RAM (2x 2048 MB) Corsair XMS2 PC2-800
Seagate 250 GB HDD...
OS: Windows Vista x64
The problems with Lock On FC also the following: I am always getting CTDs, sometimes along with an error message, sometimes without. Most of the time, this happens in dogfights or generally when there's a lot of action in the game. That's not really funny...
On my old PC (Athlon 64 3400+, Radeon 9800 XT, Vista x86 --> 32 bit), i did not experience these kind of problems. The game ran of course slower, but stable.
The other problem are graphical glitches:
There are white lines on the marginal sides of the wings and fuselage. These are flickering. That does not really look good. I tried different drivers with my Radeon HD 4850: Catalyst 8.6, 8.7, 8.7 DNA, no change.
Anyone any idea? Do these graphical errors also occur with nVidia cards?
BTW: EECH 1.10.2 also makes problems, just like others described it here: http://www.simhq.com/forum/ubbthreads.php?ubb=showflat&Number=2525979&fpart=3
All other games run fine! I played Call of Duty 4 (great game!) without any problems; Armed Assault works fine, Crysis too.