sean.wlx+gog: I think this is simply a game bug and has nothing to do with affinity/resolution/graphics settings/priority/physx/drivers/overclocking etc. I tried a bunch of these posted fixes and at first, none of them worked. Then the affinity trick suddenly started working. I then restarted the game without the affinity mask and IT STILL DIDN'T CRASH.
I think the reason so many people have so many different fixes for this is because it's just placebo - it's a 1 in 4 chance that boss is spewing clocks at the first wave of hiss, and after the first wave, it's pretty easy and natural to kill them before the clock spew. And changing graphics settings/affinity etc could be affecting the game's RNG so that it doesn't spawn hiss in the path of the clock spew.
I believe this is correct. I too had a consistent crash at the very start of the fight, right when the Anchor first opened its mouth. I've tried all solutions from this and the other discussions, and the last one, which was Vista compatibility, seemed to work. After I played a bit in the non-crashing fight, I died which caused the game to update my save. I then removed the Vista compatibility and the fight didn't crash anymore, so apparently something is saved in the game's save which prevents the crash from happening after it didn't crash for the first time.
After that I reverted to my older save, and indeed the crash happened again, consistently, at the same moment, with or without Vista compatibility.
So now I have an always (or almost always, I suppose) crashing save, and a never crashing save (I tested it for about 3\4 of the fight, I didn't finish it nor did I test the arcade version of the fight, but at least it never crashes at the beginning of the fight anymore).
I tried the always crashing save with the Steam version, and as expected, it doesn't crash. I also noticed that the when the GOG version loads, it shows a black screen for a few seconds between the company logos and the epilepsy warning (I think), another issue which the Steam version doesn't have. Shame on Remedy for not fixing this crash which was obviously caused when they converted the Steam\Epic version into the GOG version. :(
By the way, I noticed that the GOG version creates a file named stats.bin in the save directory, which is partially encrypted, and the Steam version doesn't use this file, it apparently uses stats.ini instead (plain text) - anyone knows what this stats.bin file is for? Is it used in-game, or for something else? I don't want to lose in-game information if I'm moving my save from GOG to Steam.