Video weirdness

[i_b_spectre]

After a long hiatus following a hard drive failure, I finally reloaded SH3 and installed GWX 3.0. Great mod, btw, kudos to the always excellent team.

Anyway, on the last two missions I have experienced a video anomaly heretofore unknown to me. It only happens when I am looking through the periscope, but the image seems to freeze, then it deteriorates from the outer edges of the periscope view toward the middle. Once this begins, it affects all other video within the game and I have to exit. The last time, I had been trying to elude a destroyer in bad weather for almost two hours, alternating between internal and external views to try and keep some sort of situational awareness. I never had any glitch switching from surface to submerged or internal views. Only when I raised the periscope and began trying to get a solution on a target. This is the same hardware and video driver I used before the hard drive failure and this never happened before. It's an old ATI 9800 Pro, so updating to newer drivers will not work. Any ideas?