Hardware issue or software limitation?

Jul 24, 2014 at 9:45 AM
Edited Jul 24, 2014 at 10:02 AM
Good morning. Just signed in to (hopefully) solve some issues I'm having with the emulator. First of all, this is my currently installed hardware (running 7 Ultimate 64bit):
  • Intel Core i7-2630QM at 2GHz (up to 3GHz because of the TurboBoost technology)
  • GeForce GT 540M (this is a laptop) with the infamous Optimus technology, sharing its 2725 MB (according to DirectX diagnostic tool) with an Intel HD chip (should be #4000)
  • a Realtek sound card
  • 4GB of RAM
Apparently, it seems that in certain situations the vps drops from 60 down to 50-55 (although it can be very noticeable, giving the fact that lots of ps1 titles are capped at 30 fps). I must say that I had in the past an analogous problem with ePSXe that was solved by changing the audio plugin, but if I recall correctly the vps drops were cadenced, regular - here it seems to be circumstantial.
I'm currenlty using a tweaked version of Pete's OpenGL driver that allows the use of GTE accuracy (and yes, I had the frame rate problem even before changing plugin); also, widescreen is on. Here's a picture of the plugin's settings (the shader has no performance impact): http://postimg.org/image/6o7ti5471/
Audio-wise, I'm using PEOpS 1.10 (yes, had the issue even before and had to change plugin because of audio distortion, but that seems to be quite common) - by the way, this is interesting: in ePSXe a broken audio plugin caused the emulator to constantly fluctuate between 60 and 58 vps, inducing a rhythmic stutter; changing plugin solved the issue, correctly locking the vps at 59.9. Here's another picture: http://postimg.org/image/qktkq92k9/
So, here's the thing: I would consider this an hardware failure because Optimus is, au fond, a broken mechanism good for nothing but migraine (even though it does work flawlessly with ePSXe and almost every other emulator); as I said, I would - however, if I set the fps limit to 200 (or don't use it altogether) I don't experience any performance loss. To be precise, I do - that is, vps is still subject to constant changes, but it does not drop to, say, anything below 100 vps; however, this isn't always true.
There are two games that I'm trying to play with GTE accuracy and widescreen hack on, namely "Spyro the Dragon" and "Crash Bandicoot 2: Cortex Strikes Back", both NTSC copies. They act like I said: unstable vps that apparently isn't bottlenecked by my setup. I can confirm that there is a very slight improvement in performance disabling the GTE and widescreen hacks, but still they perform poorly (at least compared to ePSXe, where the two run flawlessly); yet, the games' performance skyrocket without a problem if the emulation is set to higher frame rates.
Other games don't seem to be affected by the fps change at all (especially 2D or 2.5D games, like "Rayman" or "Tombi"/"Tomba"), running at 60 (59.9) vps anyway (also, it seems like menus and loading screens cause this behavior no matter witch game). Other games don't run optimally in spite of everything (like "Tekken 3", a game that runs natively at 60 frames per second, wich can't achieve a decent framerate anyhow, even if forced to run at higher rates; in this case I recognize a coupling of hardware failure and poor optimization, because it does act peculiarly in PCSX-R despite its immaculate performance in ePSXe - wich doesn't support widescreen or GTE for that matter).
It's like the emulator is acting as its real counterpart would (id est badly) if forced to output at 16:9 (again, the issue is mildly mitigated by disabling widescreen), yet the frame rate can (in most cases) be boosted, and the emulator's performance change accordingly. It is so baffling it's intriguing. As you would expect, open landscapes with lots of NPCs and the like (a common scenario in Spyro) are the most problematic performance-wise.
I hope this can be easily solved.

Kind regards.