I've tried both 3DFX mode and standard. In both these modes, if I use my desktop resolution (1600x900) the game is slow to the point of unplayable, with the audio constantly skipping as well.

I've never had a problem running other DOSBox or 3DFX before.

So far, in 3DFX mode, I've eliminated the skipping sound and sped the game up to a playable level by lowering the resolution in the setup to 800x600.

Does anyone have any ideas as to how I can eliminate these problems whilst maintaining a high resolution, please? BTW - I've tried adjusting the cycles to no avail :(

*Edit*
The best compromises I've found so far - while keeping a decent appearance - are:
1. To run it in software mode, highest detail, windowed - this dramatically boosts speed.
2. Running in NGlide (3DFX) mode fullscreen (as I don't know how to get windowed with 3DFX) but at 640x480 resolution. Of the two, the first option results in the better performance.

What's baffling is that if I set everything to max and go fullscreen, standard software rendering performs by far the worst. Another problem with software mode is that the game hangs in DOSBox with a flashing text input prompt every time I quit, so I have to 'Alt+TAB' or press the Windows key and then manually close the program.

It's worth noting I've tried running as an administrator and every compatibility mode there is, none of which helped.

Here are my specs: Windows 8.1 64-bit.
Processor: Intel(R) Core(TM) i3-2120 CPU @ 3.30GHz (4 CPUs), ~3.3GHz
Memory: 4096MB RAM
Available OS Memory: 3966MB RAM
Page File: 2045MB used, 3775MB available
DirectX 11

Graphics: (Crap beyond belief) Intel HD 2000 (never again).
Display Memory: 1664 MB
Dedicated Memory: 32 MB

To anyone having similar problems getting Screamer 2 to run well, check this out; this worked for me and now it runs great! :) http://www.gog.com/forum/screamer_series/not_at_all_what_i_remember
*Specifically, look for the post by kerframil about changing the 3dfx config file. Also the post by nicolascy (mentions getting the latest Nglide wrapper) - I did both and now the game is perfect (at least in 640x480 res). Huge difference!