I have a box with cantos 6, it has a VGA and 2 divi connections, I also have 3 monitors...but I can't seem to get all three to display..I am even willing to switch distorts, I tried Ubuntu and other Debian variants but nothing...I even got USB to divi connectors but nothing works(no linux drivers),it works on windows though

How many are addon cards? Some systems bios only let you select either onboard or the addon card.

I have one addon card, but not even two screens works.it displays but shows a colored screen, an I can't change it

Are you trying to drive both monitors from the same addon card?
What card is it? Have you tried the manufacturer's drivers for it?

What is a "USB to divi connector"? Are you talking about a USB video card? I've never tried those before, but I can't imagine they would work well at all given the USB (especially 2.0) bandwidth limitations.

I've got an Nvidea Quadro NVS 285 which drives two screens in cinema mode (one big screen), can't use the onboard VGA though. I've also got an old Matrox graphics card which handles four monitors somewhere but I've never been able to get it to work.

Check out video wall adapters here but I think the cost would be prohibitive, you're also going to need a really powerful system to push all the video about I'd reckon so, again, a high spec multi core CPU system may be needed? As to software to drive it, I'm afraid I've no idea.

I read somewhere that Terry Pratchett, The UK author of the Discworld novels, has a set up with six monitors so it may be possible. When he was asked why six, he apparently answered, "Because I can't fit eight on the desk!"

Play Bonny!

Is it the color of desktop?

I apologize for the late reply here is my lspci output below.I have a onboard , VGA and DVI as well as a PCI radeon .I also bout 2 usb to DVI video cards(ULTRA usb graphics Adapter), they work well on windows,but linux I'm having a hard time getting success.

I have not tried manufacturer drives , the motherboard came with only windows drivers.


00:00.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Root Complex
00:00.2 IOMMU: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) I/O Memory Management Unit
00:01.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Trinity [Radeon HD 7660D]
00:01.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Trinity HDMI Audio Controller
00:04.0 PCI bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Root Port
00:11.0 SATA controller: Advanced Micro Devices, Inc. [AMD] FCH SATA Controller [IDE mode] (rev 40)
00:12.0 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB OHCI Controller (rev 11)
00:12.2 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB EHCI Controller (rev 11)
00:13.0 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB OHCI Controller (rev 11)
00:13.2 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB EHCI Controller (rev 11)
00:14.0 SMBus: Advanced Micro Devices, Inc. [AMD] FCH SMBus Controller (rev 14)
00:14.1 IDE interface: Advanced Micro Devices, Inc. [AMD] FCH IDE Controller
00:14.2 Audio device: Advanced Micro Devices, Inc. [AMD] FCH Azalia Controller (rev 01)
00:14.3 ISA bridge: Advanced Micro Devices, Inc. [AMD] FCH LPC Bridge (rev 11)
00:14.4 PCI bridge: Advanced Micro Devices, Inc. [AMD] FCH PCI Bridge (rev 40)
00:14.5 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB OHCI Controller (rev 11)
00:16.0 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB OHCI Controller (rev 11)
00:16.2 USB controller: Advanced Micro Devices, Inc. [AMD] FCH USB EHCI Controller (rev 11)
00:18.0 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Function 0
00:18.1 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Function 1
00:18.2 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Function 2
00:18.3 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Function 3
00:18.4 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Function 4
00:18.5 Host bridge: Advanced Micro Devices, Inc. [AMD] Family 15h (Models 10h-1fh) Processor Function 5
01:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 06)

From what I can tell, the Radeon HD 7660D is the built-in graphics driver in your processor.
http://www.notebookcheck.net/AMD-Rad...D.90028.0.html

I'm not seeing any other video adapters in your lspci output.

Which device are you trying to use to drive the two monitors?

Maybe disabled in bios.

I am not sure why its not showing..hmm , but thats another issue.I am just now trying to connect only with the onboard radeon card, and it works showing both screens at boot, but when logged in , only one screen shows and the other monitor is blank.

I'm afraid I have no experience with Radeons in Linux. All of my Linux multi-monitor experience has been with NVidia, and all you do there is install the NVidia driver and run nvidia-settings to set up the layout, resolution, etc.

What make & model of computer?
Who is mobo manufacturer?
It seems you have addon card disabled in bios.

I thank you all for your comments and trying to help The issue was I had to install the linux driver from the AMD site.I check the CD and it didnt have the linux drivers, so I didnt bother to check else where, so thank you for leading me on the correct path.