Research Room Freezing Problem

[Robby]

So I've seen this problem mentioned around in the forums, but haven't seen a solution to it. And when I was running through Penumbra again, I bumped into the same issue. Probably won't be fixed, considering the time, but still.

Firstly, my PC is:
CPU - AMD Athlon II X3 450
GPU - AMD Radeon HD 6670 (2GB)
RAM - 10GB @ 1333MHZ

Game runs ~50-60FPS on med-high settings combination overall. But when I enter the Research Room, the FPS dips to like 1 every 5-10 seconds. Pressing ESC immediately opens the menu and FPS goes back up to 60. This issue seems eerily similar to the issue I experienced when I made an accidental "timer duplication" in my Amnesia custom story, but it could be something else.
Things I've tried:
1 - GPU driver update I cannot do since I already have the latest one, and there hasn't been an update in a long time.
2 - PC restart, Steam restart, game restart, etc. No difference.
3 - Tried reloading earlier save, from the start of the game even. Nothing.
4 - Verify game cache. Nothing.
5 - Different game difficulties. Nothing.
6 - Tinker with game graphics options for a while. Nothing.
7 - Tried my onboard GPU (HD 4200, I think it is). Despite obvious framedrops, the real issue is unchanged.

I lost my most recent saves when I migrated the game from my SSD to HDD, but what I'm planning to do is "move" the level's script file away and see what happens. In the meantime, anyone have an idea as to what this is still?
EDIT: I have the game on Steam.