When you boot your computer into MS-DOS, it is effectively running in 16-bit mode (or 32-bit, if you're running a protected mode game like Doom). It does not matter that your CPU is 64-bit.

However, your CPU is hundreds (maybe thousands?) of times faster than the hardware for which Doom was originally written. Running MS-DOS on this computer is a fairly terrible idea. You should not expect many things to work properly. There is very little reason to do this. (Can you even use your sound card?)

There should be some options in your Mouse control panel in Windows relating to the PS/2 mouse (namely Sample Rate and Input Buffer Length). I haven't used CuteMouse in a while so I'm not sure if it has similar options. You might need to use an older version of CuteMouse; I think the new version has some problems.

Also, if you're using a ball mouse it might just be dirty.

I'm not really sure if it's 16 or 32-bit, but here's a screenshot of Dos booting, if that helps at all:

As you can see, it fails to find my Sound Blaster PCI 64. Surprisingly, Doom runs at full speed, as does Doom II and Heretic.

I don't know your system specs, but you will almost certainly never be able to get anything working with your sound card in DOS on this computer, except maybe XMPlay (a specialized music player). This is a fundamental limitation of modern motherboards starting around the Pentium 4 era (which I might add are 32-bit): even if they have PCI slots, they simply lack the legacy device access that SBINIT (and SBEINIT) depends on. Unfortunately, no one's ever really gotten to the bottom of the specific details – something to do with SERR to NMI routing.

I might add that SBINIT/SBEINIT requires EMS to work, which means you need EMM386 and HIMEM (or preferably JemmEx, which is much less likely to choke on the comparatively enormous amount of RAM you have). But that's a secondary issue.

In any case, if running DOS games with sound is important to you, you might as well give up now on trying to get your PS/2 mouse to work – you might get your mouse working one way or another, but not sound.

Mrs. Nesbitt wrote:

I'm not really sure if it's 16 or 32-bit

DOS is 16-bit, period. You've probably heard that you can't run 16-bit programs under 64-bit Windows, but that's just how 64-bit Windows works. You can just as easily run a 32-bit version of Windows on a 64-bit CPU and then run 16-bit programs from 32-bit Windows; the primary limitation is that 32-bit Windows can generally only use a maximum of 3 GB of RAM.

That machine will be fast enough to play Doom comfortably in DOSBox 😀

Alright. Well, I was looking to get original hardware eventually anyway. I just wanted to do some experimenting in the mean time. Thanks for the help.