For some reason when I run Second Sight I get really low FPS which seems to be absolutely fixed at a certain figure. I've been watching it in FRAPS, and I've seen it stick at 22 and 32 before, but now when I run it it always stays at 16 FPS no matter what I'm doing. I've tried using the nvidia control panel to force v-sync on to try and fix it at 60 FPS, but that doesn't work either. What's weird is that I can force on anti-aliasing just fine, and that works, but v-sync doesn't come on.
I'm not sure what specs are relevant since my computer should easily be able to handle this. I think the possible culprit might be my OS, but here are limited specs. If there's anything else relevant let me know.
Vista x64 SP1
Core 2 Quad Q9550
4GB ram
nVidia GTX 260 in PCI-Express and 6200 in PCI (running multiple monitors)
driver version 178.08

Yup, I have done. I posted this hear in case anyone else is getting the same problem - and if I find a solution I can put it here for others to use.

have you tried running the OS in 32bit mode?

I'm not sure what you mean. The system is set up as x64 - all the drivers installed are 64-bit, I don't know of a "32 bit mode" that's available - 32 bit applications just run under emulation. If you could tell me what I'd need to do, I'll give that a try.

I'm not sure what you mean, the program already runs in 32 bit mode under emulation, since there's no 64 bit binary. What are you wanting me to try exactly?

Great, I tried your solution and it actually helped :). Game runs at full speed now :D.

Got it working fluently by simply rebooting the PC. Odd.

Do wish it will be available again in here or Steam.

Something is very wrong with this game. I'm getting the same problem as the OP.

When I first installed the game from GOG, it was running smoothly at 60 FPS. The next day when I played it, the FPS had dropped to 51.

That was a few days ago. Today when I started it up, it was down to 32. I assume if I play it again tomorrow, it will be down to 22.

I have a strong feeling that the FADE DRM that was in the retail version of the game is also present in the GOG version, and was not removed properly before it was put on sale. Is that possible?

I have already tried uninstalling and reinstalling the game, which did not work. I only have a single video card in my computer - a GTX 980 Ti - so I can't disable it temporarily to try and fix this. Restarting my computer also did nothing.

I will send in a support ticket to GOG to see if they can check this. It would be a major problem if the FADE DRM is still there and could not be removed.

I'm 100% sure the fix used to be permanent, back when I was on 8.1 I only had to do it once.

Now? I did the fix two days ago, bam, 60 FPS. Today, (two restarts later) it's down to 42 FPS. I wonder if it really related to the DRM being triggered somehow like the poster above speculates, lowering the framerate more and more for each time the game is booted seems right up its alley reading up on how it's done piracy prevention in other games. Looked around a bunch and didn't manage to find any details on how it's handled in Second Sight.

Hell I even tried a cracked exe and it made absolutely no difference.

For the record, I'm on Windows 10 now.