First, the Hardware: P4 2.8Ghz, Radeon 9800 Pro 128 MB (newly installed as of 3 days ago with then no problems).
Prior to fittng the new card I had a 9600 Pro which I was running with AGPx4 and Fast Write off with Omegav2.4.96b drivers; the Intel chipset I had would not allow a change to these settings via the ATI control panel. FS was running nicely.
Reasoning that my new card should be running on AGPx8 I loaded the latest Intel chipset on Sunday, selected the AGPx8 and, again, all was well until last night........
Idle hands etc etc. I decided to see if FASTWRITE would make any difference to FS performance. Through the ATI Control Panel I selected it, rebooted and hey presto it accepted the change. Restarted FS and the aircraft picture (on create Flight) was corrupted with triangles and distorted squares inside the fuselage area and 'lightning strikes' emanating from any extremety of the aircraft. If flight was selected, the cockpit is rock steady but all external views are zig-zagging about.
I have reinstalled FS and run it without ATI drivers when the problem disappears. I have replaced the Omega drivers with ATI cat 4.6 and the problem is back. Of note is the fact that the new drivers automatically loaded FASTWRITE 'ON' and despite trying to turn it off through the Control Panel I cannot get rid of it and I am sure that it is this setting which is causing the problem.
Any ideas out there, particularly with regard to getting rid of FASTWRITE? I should add that there is no facility in the mobo BIOS (MSI 865PE Neo 2 mobo) to alter AGP or fastwrite settings)