I'm pretty sure you can have multiple GPUs in Win98SE (I used 7800 GTX 256MB + GTX 780 Ti combo as well as single 7900 GX2 😉).
However, to switch between them as videos outputs requires disabling one and enabling the other one (+ OS restart).
You can bypass above method if you use PCI and AGP/PCI-e cards at the same time (since in most MBs BIOS you can simply choose which port should be video output).
Windows will in that case use by default card in slot you picked in BIOS.

I was going to point out that I have integrated graphics (SiS Mirage 2), but, the CMOS battery is dead, and I have to sacrifice a DDR RAM stick from the sleeping Dell Dimension 4550 since the 512MB RAM stick I had installed broke mysteriously (mainly because of a dead clock battery), and I believe the integrated GPU requires at least 512MB system RAM in order for the GPU to have its own RAM (up to 128MB), but the integrated GPU can only do 2D tasks, not 3D as it's a basic GPU, much like the Intel's Extreeeeeeeeeme Graphics.

Would there also be a way to switch the GPU settings within Windows 98SE without altering the first boot GPU from PCI to AGP or vice versa, like a program, for example, or is that not possible?

agent_x007 wrote:

I'm pretty sure you can have multiple GPUs in Win98SE (I used 7800 GTX 256MB + GTX 780 Ti combo as well as single 7900 GX2 ;)). […]
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I'm pretty sure you can have multiple GPUs in Win98SE (I used 7800 GTX 256MB + GTX 780 Ti combo as well as single 7900 GX2 😉).
However, to switch between them as videos outputs requires disabling one and enabling the other one (+ OS restart).
You can bypass above method if you use PCI and AGP/PCI-e cards at the same time (since in most MBs BIOS you can simply choose which port should be video output).
Windows will in that case use by default card in slot you picked in BIOS.

How did you get the 780Ti working in 98SE?

What did you do to get it to boot with a video card that has more than 512MB of RAM?

cyclone3d wrote:

agent_x007 wrote:

I'm pretty sure you can have multiple GPUs in Win98SE (I used 7800 GTX 256MB + GTX 780 Ti combo as well as single 7900 GX2 ;)). […]
Show full quote

I'm pretty sure you can have multiple GPUs in Win98SE (I used 7800 GTX 256MB + GTX 780 Ti combo as well as single 7900 GX2 😉).
However, to switch between them as videos outputs requires disabling one and enabling the other one (+ OS restart).
You can bypass above method if you use PCI and AGP/PCI-e cards at the same time (since in most MBs BIOS you can simply choose which port should be video output).
Windows will in that case use by default card in slot you picked in BIOS.

How did you get the 780Ti working in 98SE?

What did you do to get it to boot with a video card that has more than 512MB of RAM?

I didn't wrote I used GTX 780 Ti in Windows 98SE...
However, GTX 780 Ti was installed in PC while it was running Win 98 SE.

As for 512MB+ VRAM, GX2 is simply special in this case :

bjwil1991 wrote:

I'm planning on re-installing my Riva TNT2 M64 card (ASUS brand) AGP card for games that support it since the GeForce2 MX400 doesn't play nice with some of the older D3D games and install an EVGA branded GeForce 6200 PCI card for the T&L games, such as Command and Conquer: Generals, Joint Ops: Typhoon Rising, NFS: Hot Pursuit 2, Blackhawk Force Down, and so on.

I have a KVM switch box that I can use to switch the video signal around, however, I have no idea if that'll work or not. Should I just use the GeForce 6200 (AGP) and the VooDoo2 card, or use the GeForce2 MX400 with the VooDoo2 card?

If my assumption is correct, the only way to have multiple cards installed would be to have the same brand and model, correct, or is there a program that changes between cards for certain games?

You can use whatever (well, probably there will be exceptions) card combination in Windows 98 SE. I did that in the past, and still doing it in some builds now. Tried several different cards together (matrox, 3dfx and S3 PCI cards with ATI, 3Dfx and nvidia AGP cards) without a single failure (my cards are not so modern PCI and AGP cards, to say the truth, though)

Using a PCI and an AGP card combination will be easier since you can choose the primary card from your BIOS (AGP or PCI). It is easy to have one as primary and the other as secondary permanently, but interchanging between them will require a reboot + BIOS setup change. I also have no idea how Windows 98 will behave, it probably will require another additional boot just after recognizing the "new" card.

I would suggest a multiboot configration; one W9x partition with one card as primary, and a second W9x parition with the other card as primary. So you only need to boot once and change the primary card from BIOS setup and choose the appropriate Windows 98 to boot from your multiboot menu.