Baoran wrote on 2020-05-15, 18:41:

I am sure this has been asked before, but I couldn't find a thread using the search function.
Would it be possible to setup dual OS system when you have 2 video cards in a way that when you boot to win98se it would automatically use a PCI video card in the system and when you would boot to winxp it would automatically use an AGP (or maybe even PCI express) video card?

Just don't install drivers on for the other card on the other system, you will have to have 2 monitors plugged in, and if you disable the device it will stop doing "New hardware detected" when you boot the pc.

Yes, that's possible. In device manager, select that the card is not available in all hardware profiles and then select that it is disabled in this hardware profile. On the second OS, do the same with the other card. Works fine, did that in one of my builds, too.

Only drawback is that you get a warning beep while the OS boots. At least if you not have monitors connected to both cards all the time.

Thanks. Just one more question. Do adapters exist that would allow both video cards to be connected to a single monitor?

Of course, there are video input switchers.

But the more easy solution would be to connect one card via VGA and one via DVI. You normally have both on most non-CRT monitors anyway.

derSammler wrote on 2020-05-15, 18:59:

Of course, there are video input switchers.

But the more easy solution would be to connect one card via VGA and one via DVI. You normally have both on most non-CRT monitors anyway.

I only have one 19" CRT monitor for all my retro PCs. I basically currently have 4 PCs and just just one monitor because of lack of space.

Then look here:

https://www.amazon.com/s?k=vga+switch+box&ref=nb_sb_noss_2

Baoran wrote on 2020-05-15, 19:07:

derSammler wrote on 2020-05-15, 18:59:

Of course, there are video input switchers.

But the more easy solution would be to connect one card via VGA and one via DVI. You normally have both on most non-CRT monitors anyway.

I only have one 19" CRT monitor for all my retro PCs. I basically currently have 4 PCs and just just one monitor because of lack of space.

You can get a simple, 2-Port Auto Switch KVM Switcher. It will Auto switch when it detects a signal on one of the inputs

Or a not so simple 4 port kvma (where the a means audio), I have a Lindy one and it works well.

Baoran wrote on 2020-05-15, 18:53:

Thanks. Just one more question. Do adapters exist that would allow both video cards to be connected to a single monitor?

I used a VGA "splitter cable" once to connect two cards to a single monitor. Of course it won't work at all if there's any kind of signal coming from the card that is supposed to be inactive.

Thank you all for the advice. I had been considering getting a big kvm switcher to connect all my retro PCs some day, but I was wondering if a simple splitter cable would be more smart thing to do for a single pc that would have 2 video cards. That way if I will get kvm some day I would not need to use 2 ports of the kvm for a single PC.