TF2 Maps flashing white?

[Knowing]

You can see where the discolored road strip is, but it's hard to get pictures of the game doing this because it strobes really fast. Any idea what's causing this?

[Zork Nemesis]

Would it be possible to record this in action with a video recording program? A demo file won't work in this case since demos run off the engine and therefore on a correctly working computer it won't show issues.

A couple theories:

Texture error: could've happened when you installed a mod or something. Try verifying your TF2 install and see if there's a bad file in there.
Shearing: A case that occurs if you have the game attempting to display more frames per second than your monitor/graphics card can actually display; though the cases of shearing i've seen were far more pronounced and not just a flickering patch. Enable VSync if it's not to see if this fixes anything. If Vsync is already enabled, then shearing is not your issue.

[Knowing]

I validated the files. They're good.
I never have VSync on.
It stops when fraps starts to record it ._.

[Zork Nemesis]

I never have VSync on.
It stops when fraps starts to record it ._.

It likely is shearing then, Fraps will limit your FPS to 60 when it records. When I had a similar issue I found it stopped when I enabled Fraps recording. Turn on Vsync and see what happens.

[Knowing]

Turned it on. Nothing T_T