I've run various flavors of Linux (Slackware, Ubuntu, ...) using KDE, Unity and Cinnamon desktops with 2 monitors, no problem. I'd like 4 monitors and I'm toying with the idea of either adding a 2nd card that will add 2 more monitors (if that's possible), or buying a video card that supports 4 monitors; for example, Radeon 7750 SFF 4 Monitor. This card is somewhat expensive ($180) for workstation (not gaming) use, so I'd first like to have some feedback as to whether anyone knows if Linux supports this setup.

I have had 3 monitors working before, but I havent tried 4. I don't see any reason it wouldn't work, though. Given you have capable hardware

Were your 3 monitors all via video card or were one or more a USB VGA video like DisplayLink?

I had 2 Asus 9750's. Two plugged into one card, the third in the other. They were all connected via dvi

I had 3 monitors on an AMD 6000 series IGP so 4 should work on higher end cards.

Thanks all, I think the answer is "yes". Now I need to buy a card and try it!

I'm back for advice. I'm looking at the ATI FirePro 2450 Multi-View 512MB video card: https://www.newegg.com/Product/Produ...82E16814195083. Will this run on Slackware? It uses the ATI chipset. Features I like include low profile (need for my case) and it will support VGA which means I don't have to replace my 4 monitors or buy adapters.

I'm also looking at the Sapphire GPRO 4200: https://www.newegg.com/Product/Produ...Q&gclsrc=aw.ds. This uses the AMD chipset and has a lot more memory.

Should I avoid Nvidia chipsets?

The FirePro needs PCI Express 2.0, the Saphire is PCI Express 3.0. My motherboard (ASUSTeK M4N68T-V2) has:

1 x PCIe x16
1 x PCIe x1

Will both of these cards work?

btw - I don't do gaming. This is strictly for business and program development use. My monitors are currently set to 1360x768, which is fine.

Even if the hardware doesn't work directly, you can use Xdmx to use up to 16 monitors(X forwarding and multiple machines over a network). Although Xdmx hasn't seen much attention since 2004. I tend to go the reverse route and use Xdmx + Xephyr to break my one screen into two or more that are stacked vertically. So I can have a really tall xterm, which can get you an 80x405 line xterm on a 1080p screen with an 8x8 bitmap font. Which can be nice for looking at some source code. But you lose hardware acceleration with various input quirks due to the changes in X not mirrored in abandoned Xdmx. So not that useful beyond "looking" at source code. Although it still works and has uses.

I suspect that it will work in your case as long as you don't mix and match GPU brands. Although you may have to play distro roulette to find one that works out of the box the way you expect it to. Most tend to default to the lowest common denominator (1024x768 in the case of my 1366x768 laptop + 1080p hdmi monitor) IMO. Using xrandr can help make almost any distro bend to your will. Which is what I use to make my 1080p the papa bear so I can turn off the laptops LCD in debian. Some distros like arch and fedora seem to default to that configuration, but have other annoyances that push me back to debian.

For a multitude of reasons not related to my 4 monitor issue, I'm trying to stick with Slackware. I could just buy the cheaper card (ATI FirePro 2450) and see what happens, but If someone has experience with these on Slackware, I'd like some pre-purchase info. Xdmx sounds interesting, but I don't think that's what I want for now.

In terms of NVIDIA, they refuse to write an open source driver for their hardware and insists on their closed-source driver. So the answer is that, if slackware includes this (closed-source) driver and/or it is installed on slackware, I cannot see any reason as to why you would not be able to use a NVIDIA based card (as I'm also one of those people).

Which version of PCIe does your motherboard support?

You should only have issues IMO, if the four monitors are pulling from different graphic drivers. As in a mix of amd/ati, intel, and nVidia. If all four monitors are on the same GPU card you're golden. Assuming that the GPU is multi-head and not outputting the same thing to all ports (used to be what older gen cards and laptops did, aka single head GPU with multiple ports). That being said, some drivers are better than others. When you start using multiple displays, you find all the bugs on the inferior product(s). Basically if it does it under windows you should be able to do it under linux. And if the open / non-proprietary driver does it, it probably does it better. Check other forums and technical specs though. Some might have 4 ports and only be able to drive 3 independent displays. You'll have 4 outs, but 2 will be the same content.

It looks like the 2450 is a quad (4) output card and should work. 4x DVI, or 4x VGA (adapters?)

https://www.amd.com/Documents/ATI_Fi...Data_Sheet.pdf

The gpro 4200 says max 4 outputs, not quite as definitive. 2x DVI, 1x HDMI, and 1x Display Port

http://www.sapphiretech.com/productd...4C1A6&lang=eng

I'll do some checking on whether Slackware includes NVIDIA drivers. I don't know. As to which version of pci, all I have to go on is what the spec sheet said, which was that PCIe x16 and PCIe x1 bit. I'm assuming that probably means not PCIe 3.0, but that's a guess.

Shadow7: I guess we'll find out. I went ahead and ordered the ATI card. I should get it this week. Will post findings.

I have 5 monitors running on Kubuntu. 4 monitors are running off a 3 year old NVIDIA card at 1920x1080 and the other is running off a display port -> HDMI converter on the mother board - this is the primary monitor. I didn't have one problem on the first install when I had all 4 monitors attached to the card and then later added the 5th once the OS was up and running.

Here is a card that looks like a good deal:
GIGABYTE GeForce GTX 1050 Ti DirectX 12 GV-N105TWF2OC-4GD 4GB 128-Bit GDDR5 PCI Express 3.0 x16 ATX Video Card $159.99

GIGABYTE GeForce GTX 1050 DirectX 12 GV-N1050OC-2GD 2GB 128-Bit GDDR5 PCI Express 3.0 x16 ATX Video Cards $119.99 w $10 rebate - $109.99 after

GIGABYTE GeForce GTX 1050 DirectX 12 GV-N1050WF2OC-2GD 2GB 128-Bit GDDR5 PCI Express 3.0 x16 ATX Video Cards $129.99 w/ $20 rebate

The bottom 2 are almost identical except the third one is over-clocked a little so if you don't need that extra 1% in clock speed then go with the standard (second) unit as I would suspect it to be more stable.

Depending upon the monitors you have you can get cables that connect from whatever the card port is, to the port on the monitor. if the card port is DisplayPort and themonitor DVI - then get a DP -> DVI cable, if port is HDMI and the monitor is DVI then get a HDMI-> DVI cable - etc. These can be about $10 each for a good 6-10ft cable.


Here is a list of all the cards at newegg that support 4 monitors

What monitors are you running to this unit?

If you can afford the first one, I would opt for the 4GB unit as I have a 2GB and have had some GPU memory issues at times with freeze ups and a black sceen. IDK if it is from lack of RAM, but this should not hurt.

cilbuper: Thanks for that great info! I did received the ATI FirePro 2450, but it was not low-profile , which I need for my box. I re-ordered the low-profile model. I might go ahead and test with the high-profile one with case lid off, just to see if it works. I'm a bit concerned because it has only 512M, but we'll see. I've got a VGA on the motherboard and it would be excellent if I could do 5 monitors too, like you. If my ATI card doesn't work out I'll definitely check out the cards you recommend.