Maximum PC

So i have a pair of sapphire Radeon 5870s, each with a pair of DVI, a HDMI, and displayport outlet. I just picked up a trio of Samsung 550 series 27" LED displays. They have HDMI and VGA outlets, i got 3 VGA->DVI converters and plugged 2 into the first card and the 3rd into the 2nd card. With my cards running Crossfire only 2 of the monitors will work, the ones plugged into the primary card. If i disable crossfire then all 3 work, but not as nice for games because Crossfire is off. Is there any way to get all 3 cards running with Crossfire enabled, when they are plugged into 2 cards?

I don't know about this, but I'm sure 3+ monitor mode wants to output DVI. In which case, you can get DVI<->HDMI converters for pretty cheap.

You are essentially combining the GPUs by running them like that so in the end, you're restricting the outputs to the primary card

I think to get all three going, you would need to use the outputs on the primary card, so one of these will need to use either the HDMI or display port...and even then that may not work as there might be a hardware limitation of the card to be only capable of driving two monitors.

bringing this back up as i went out and got 3x HDMI-> DVI adaptors, yet am still having the same problem, plugging 2 of them in via DVI to the 1st card, and the 3rd monitor into the 2nd card, with crossfire OFF works. BUT if i enable crossfire, only the first 2 screens work, and if i switch the 3rd monitor to regular HDMI (so its 2x DVI and 1x HDMI into the main card) then the computer detects it, but wont let it be enabled, it shows 3 screens but the 3rd (the one on HDMI) as disabled, and wont let me enable it.....any ideas?

Or did you not like that answer?

Well, theres tons of stuff about using Nvidia cards for 3D gaming like this, running multiple monitors as one giant screen, using ports on more then one card, in SLI, yet its not working for me. I know its possible im just wondering if I am missing something, or if anyone knows if 5870s arent capable of running this

And SLI equates to Cross Fire how?

Simply put, Crossfire restricts you to use the primary card's outputs. Below are a couple of threads on this.

http://www.tomshardware.com/forum/35517 ... fire-setup

http://www.techsupportforum.com/forums/ ... 01126.html

Well they are roughly the same technology, but im more curious now as to why my 3rd monitor wont activate when all three are plugged into the same card...2 via DVI and 1 via HDMI, and the HDMI wont work....

Because single graphics cards only support two simultaneous outputs. Radeon HD will output to more... if it's an EyeFinity edition one and if you use DisplayPort.

Kind of wish you would've mentioned this before




This is accurate. In shorter terms, the HDMI and DVI share a resource and are not independent of each other. The other DVI port is independent.

i did mention it a few posts up, though i think i may have worded it poory sry! So i think i need to get a HDMI-> DP converter now....ugh so many cables! lol

Hold up, unless it's an EyeFinity AMD card, it won't support more than two displays.

i googled my card
http://www.sapphiretech.com/presentatio ... =287&lid=1

and it shows that it can do eyefinity, even with the ports it has, but i did notice what was mentioned earlier is that atleast one screen needs to be on Display port...

Wow...it even says on the system requirements tab

To support 3 displays, one of the monitors has to support DisplayPort.

im doing a total facepalm for not looking at that before posting this