I know when the game first came out I had to keep the details turned down pretty far to keep the game playable. The game would still become a slide show during big battles with lots of effects happening.
I still don't have a killer PC but Sacrifice runs without a hitch. I've maxed out the settings and I never get less than 60 fps. I'm assuming V-sync is on default since it never goes above 60 either which is fine by me.

I think the game had pretty high graphics requirement when it was launched.
I even bought a Geforce 1 SDR to play Sacrifice & Messiah back then(I was using a 3dlabs Permedia 2 card before that).
Nowadays, even Intel GMA 950 can run this game pretty well. :)

Hmm, stange.
I have a big problems with perfomance of this game still. I've set all Video setup to MAX, so in game menu it's like 5fps, inside game fps is flowing (tutorial 1) from 10 till 23 fps. If you do any turn (A, D or mouse) fps is extremely fast start to decrease (4-13fps). If you moving just forward or backward (W or S) everything is something like more OK.
I'am alone or some "luck" people got it too, and even maybe fixed it?
I have Vista 32, 8600M GT, 2.2GHz Dual core

Try turning VSync (vertical synchronization) to always on or off, maybe this will make a difference. Setting affinity to one core may help as well, or even a certain compatibility mode or running the game by "run as Administrator"...
Something just occurred to me... Is it the same when you launch it through "Direct3D HAL" and "Direct3D T&L HAL"?

Mine is the same. I have a feeling it has something to do with the new nVidia drivers. I run an 8800GTS 512, and it just runs like a dog unless I have all the settings as low as they go. I could actually run Sacrifice better on the machine I had when it came out! I tried running it on a single core and changing the compatibility mode too, but that didn't change anything. The killer is the detail setting.
I think getting old nVidia drivers would be the key, but getting old enough drivers that also work on Vista/7/64x is a bit of an ask.

I have Win 7 64bit, C2D E6420, Radeon 4870. Played gog version few weeks ago Sometimes I saw little graphical glitches and I already tried game 2-3 years ago on XP & GeF 7800GTX and there were glitches too...