Has anyone ever installed an ATi and nVidia card on the same rig? And been able to use dual monitor that way? Cause I have an ATi card that I can't get rid of and I need an nVidia card to install Linux and was wondering how much of a pain this type of set up would be. I would only need to use the nVidia card for the second monitor when using Windows and as the primary monitor in Linux with the ATi card not used at all.

I don't think that you can install an ATI & nVidia card on the same computer because they require the use of two different drivers, not to mention that the hardware is different for each. I'd recommending buying a card that has two outputs.

I have an x1950pro agp... It's just that I can't get the drivers to work with Linux, but I don't want to sacrifice gaming performance in windows. It's either buy a cheap PCI card or spend 1000$+ on a whole new computer. I've seen matrox has these external video switches but they cost 200$+ but I doubt I'd get any 3D performance that and I don't know if there's any other alternative?

If you want 3d performance, you must install the 3d drivers from ATI.

http://ati.amd.com/support/driver.html

Well, I tried installing the official drivers(fgrlrx) and the kernel drivers(radeon) and neither of them will work as neither of them support my card. Not to mention ATi's already lackluster support of supposed supported cards and reading through the documentation most of the supported cards don't even get hardware 3D at all. The only true solution to get 3D working in Linux(at least, IMO) is to use an nVidia card. Now, I don't need an enthusiast class card for anything I'm going to be doing in Linux. I just want to be able to play movies and not have them stutter constantly like it does with the mesa drivers. And buying a whole new computer just to have reasonable performance in Linux is ridiculous.

My only problem is that I'm worried I might have to go into the BIOS to switch the initial display adapter everytime... or if using ATi and nvidia at the same time is at all possible. I don't really see any technical reason it isn't possible, I just thought someone might have tried this solution to the ATi driver issue and known how to do it. Another concern is getting dual monitors without using a KVM switch, though I think that might be impossible as my CRT has only one video input and I'll just have to swallow my finickiness and use one anyway.

OH, if anyone needs this info.. specs are: abit ic7g/p4 3.4ghz/ati radeon x1950 pro agp/auzentech xmeridian and was considering getting a 6200 PCI card.

I do not know about slack but with Fedora we run dual head a lot. You just alter you xorg.conf. Essentilally you just write two of them combined. Monitor0 and Monitor1, Videocard0 and Videocard1, Screen0 and Screen1, etc.

Ok, cool thanks

They each install their own GL libraries, and sometimes some other stuff I can't even imagine.
From my experience, after installing nVidia official drivers, the only way to go back to kernel radeon driver is a clean install.
I was not able to weed out all the changes made by nVidia drivers on each of my attempts.