Horrible texture 'flashing'

First, let me say I am aware of the normal 'flashing' that this game has always had when it comes to anti-aliasing and some long-distance rendering, however what I'm seeing these days is entirely different from that.

Basically, there is almost constant 'flashing' of usually irregular sections of the screen, kind of jigsaw like random shapes that flash very, very briefly. It affects all areas where textures seem to be rendered, however it doesn't seem to affect the sky.

Yesterday it happened as my character was stood by a wall in Al Zhabi and I was able to clearly see what's going on (usually it happens in textures some distance away and it's harder to make out).

What was happening was that a section of a window frame (as in a building window frame) was continually being rendered, and then not, such that the brickwork 'flashed': clearly the wall seems to be one graphic element while the window frame is layered on top of it. Note it wasn't the whole frame, just most of the left vertical and a small part of the adjoining bottom horizontal, the rest of the window was perfectly 'still'.

I've been playing since '05 using a variety of hardware but only began to see this when I picked the game up again after not playing it for several months. I play on two PCs both of which are as they were when I played before, the PC with the problem is using an AMD 7870, while the PC where it isn't a problem is using an Nvidia GTX 580.

This is more than simply cosmetic, it's so frequent and noticeable it's really annoying to have to watch.

Is this anything that's known? I've tried search "flashing graphics" but that is such a general description there are scores of hits which have no relation to what I'm seeing.

Since the May update, I too have been seeing these artifacts and flashing lights in my game, and sometimes have to shutdown and start back up to get rid of them.

Sometimes it's a jagged thing, like for example the empty space behind Ploh Trishbak (entrance to castle adoulin), sometimes turns into a brown jagged wall instead of open space and a fence.

And sometimes I see these multi colored lights that sit in place when I'm not moving, but flash different colors when I move my character.

I'm using an Nvida GeForce 8600GT and I thought it was my video card dying or something until I saw your post about it too. :P