It really depends if it's 'worth it' for you. 😀 You haven't mentioned anything about your build, so I'll assume that you have a Slot 1/i440BX PC or similar.

If you're only doing it for performance reasons, then I would say that no, it's not worth it (2 x Voodoo 2s in SLI have about the same performance as a Voodoo 3 2000).
The issue is that there are no Glide-only games (that I can think of) which would benefit from an additional Voodoo 2 card. So you'd be much better off with a faster nVIDIA card + your current Voodoo 2. This way you would get the best of both worlds: much better performance and visual quality for newer games + compatibility with older titles.

Even a GeForce 2 MX 400 (which is ultra-cheap) would be a much better choice performance-wise. Or, even better, a card like the GeForce 4 MX 440/460 that is still pretty cheap but MUCH faster.

But, then again, performance isn't everything, and having a Voodoo 2 SLI build is just... cool. 😀 Especially if it's not your only retro PC (and if you can afford it), I would say that... yes, it would be worth it. 😁
The cards don't have to match (although it would be nice if they did). You can use the FastVoodoo drivers with non-matching cards and they will work well.
Banshee is not a good alternative, that one is a slow card (for games where that matters - i.e. games that take advantage of multitexturing).

This is for a Slot 1 P3 450 machine so early AGP is a possibility also. The Voodoo2 I have right now is in a Socket 7 MMX 233 box that it really has no business being used in other than curiosity (and GLQuake).

Does the Voodoo2 have any problems with passthrough from AGP cards?

Voodoo 2 cards work great when paired with AGP cards. Just for fun, I even paired them with GeForce FX 5900 / ATI Radeon 9800 PRO and have had no issues.
A Pentium 3 450 can usually be easily overclocked to 504 MHz (112 FSB - if your motherboard supports it) and it will work very well when paired with GeForce 2 GTS/PRO/Ti cards (nVIDIA Detonator version 7.76).

SLI allows using higher Resolution.

The real problem with SLI is that with two cards, you'll get double the performance penalty from texture thrashing and buffer reads (mainly involving effects in later Direct3D games like Metal Gear Solid). Banshee and Voodoo3 doesn't suffer from that (and goes beyond 1024x768 anyway)

matze79 wrote on 2021-09-19, 07:41:

SLI allows using higher Resolution.

Anything that will benefit from higher resolutions will also perform great (better) on newer nVIDIA (or even ATI) cards. Yes, even Unreal (the latest version). 😀
Let's face it, a Voodoo 2 SLI build doesn't make any sense if we're solely looking for performance. It only makes sense in period correct builds for that 'cool' factor.

800x600 is good enough for me on the Voodoo2. 😉

I prefer using higher resolution with better cards and it's pretty a waste of money doing SLI for performance unless you want an authentic experience.

I'll take the single Voodoo2 paired with a decent AGP card for now. The P3 I have on the way has what I'll assume is a basic OEM AGP card in it to get me started with.

Well I have PowerVR, V2 SLI and Radeon 7500 64Mb DDR together 👍
3Dfx almost only used for Glide stuff

matze79 wrote on 2021-09-19, 19:35:

Well I have PowerVR, V2 SLI and Radeon 7500 64Mb DDR together 👍
3Dfx almost only used for Glide stuff

How does the Radeon 7xxx series fair with DOS game compatibility?

maxtherabbit wrote on 2021-09-20, 00:01:

How does the Radeon 7xxx series fair with DOS game compatibility?

99% of games will work just fine. 😀
I tested cards like the Radeon 7500, 8500 & 9800PRO and they're actually very compatible and fast in DOS.
They don't usually have scrolling issues (well... except for some Commander Keen games that I never play anyway).
Some other games like Prehistorik have a "fast scrolling problem", that I don't even consider as being a problem - in fact, I actually like that a lot and it doesn't affect the game experience in any way. 😀

I feel that Voodoo2 SLI is only really useful for <= 1998 games. But Unreal seems to suffer from some stuttering with it so there are exceptions. It doesn't have enough texture memory.

Amongst the old renderers, s3 metal has the best graphics on unreal.
Nice 32bit and Sharp textures.
Awesome!

I would play unreal at least on a 2mx.

Radeon 7500 does fine on MS-DOS.
Also VESA Modi’s are working fine.
Playing mostly FPS with it.
Like Shadow Warrior or Redneck Rampage and many others.

My P3 450 got delivered today. I'll put the V2 1000 in with whatever AGP card it's got.

The cool factor of V2 SLI has strong appeal, but V3 2000s are much cheaper...

Dead on arrival, I can't get it to access the hard drive and i've tried several. Wasted money.

Faulty IDE controller?

Errius wrote on 2021-09-21, 04:50:

Faulty IDE controller?

I don't know. Speedsys and the BIOS pick them up, but DOS and Win 98 Setup can't find them.

TSG wrote on 2021-09-21, 06:02:

I don't know. Speedsys and the BIOS pick them up, but DOS and Win 98 Setup can't find them.

Try using a smaller hard drive.

In some cases, motherboards from that era are limited to supporting 32 GB disks or even smaller. This can usually be solved by updating the BIOS.

I've tried a 20GB, a 12GB, a 1.2GB, and a SD to IDE Adapter with various size SD cards.

I did discover it has a TNT Riva 16mb AGP video card and an Ensoniq 1868F (?) sound card.