The only thing I did to my hardware was a small OC of my CPU to 2.4GHz, GPU was left pretty much stock. That's it.
The FPS rate in Doom 3 was automatic. I guess the game detected what my hardware was capable of and bam. The darn readout in the upper right hand corner was 339fps and sometimes higher. It fluctuates really fast. Between stages, it's a dull 3-5fps, but once the action gets going again, it jumps to 200-340fps. I honestly didn't do anything else.
If those of you that have Doom 3 for PC, try this code:
Put that into the console prompt in the game and what that does is it removes the 60 FPS limit. So I guess your hardware is free to speed it up to whatever it can handle. Yeah, my PC was stressing. Big time. A nice test though. It had to shut down because it was getting too hot. I think I posted this before, but my CPU got insanely hot like around 60ish degrees before it shut down. GPU rose from around the mid 60 degrees to high 80's eventually and nearing the 90 degree mark. It took close to an hour for my machine to get this hot. If you play it on that speed for just a little bit, it won't make too much difference to your CPU and GPU, but keep playing the game for around an hour, you'll see the temps slowly go up. I'll see if I can get a screenshot of it.
I know the GPU could handle it, but the CPU fail to hold up and everything crashed. There was a long pause when it attempt to restart the PC. I got scared for a moment that something got damaged, but when it finally booted, I was relieved. I don't seen any type of horizontal tearing as the image was pretty good as usual. I did notice that when I used the code to go through walls, lol. Image got screwed up pretty big at that point. Yeah, I'm such a big cheater. I hate those doors that won't let me go through.