2 Cards - 3 Monitors - Problem

[rhym1n]

I am using 2 AMD Radeon HD 5700 Series video cards. I just got my 20 foot HDMI cable in. Last night I hooked up my HDTV to my PC, extended the display, and all 3 displays worked flawlessly together.

Today, I downloaded the most recent video drivers, and I can't get a 3rd display to work. (It did enable crossfire when the new drivers downloaded, but I disabled crossfire, and the 3rd monitor still won't work).

I go into the Windows 7 display settings, choose Extend desktop to this display on my HDTV, and it says "Unable to save display settings."

Surely the new driver would allow for 3 monitors?

 

[rhym1n]

Well, problem solved, but I have no idea why this happened...

I forgot that last night, I plugged in my HDMI cable on the bottom card to my 3rd monitor (HDTV). Today, when I plugged it back in, I plugged it into the HDMI port on my top card.

When I switched it back to the bottom card, it worked. I now have extended desktops on all 3 displays. Why in the world does that matter?

 

[i7Baby]

In crossfire (or SLI), you can only use the primary graphics card to run monitors. The secondary card is only there to assist the primary card.

 

[Mousemonkey]

Well, problem solved, but I have no idea why this happened...

I forgot that last night, I plugged in my HDMI cable on the bottom card to my 3rd monitor (HDTV). Today, when I plugged it back in, I plugged it into the HDMI port on my top card.

When I switched it back to the bottom card, it worked. I now have extended desktops on all 3 displays. Why in the world does that matter?

So you are using the primary and the secondary card at the same time? I am guessing that you may not have enabled Crossfire then, as for why it works now but didn't before only AMD can explain the mysteries of their drivers.

 

[Mousemonkey]

In crossfire (or SLI), you can only use the primary graphics card to run monitors. The secondary card is only there to assist the primary card.

Just because the OP is using two cards does not mean SLi or Crossfire is being used.

 

[i7Baby]

Most likely is. Else it defeats the purpose.

 

[Mousemonkey]

Most likely is. Else it defeats the purpose.

There are many reasons to be using two (identical) cards without using SLi or Crossfire, I do it myself. Maybe you should try googling the question.

 

[k1114]

Sli can use the second card unlike cf.

 

[rhym1n]

I am not using crossfire. That's why I'm confused as to why the primary card didn't work with 2 connections, but the bottom one does.

Again, my top card has 1 connection to a 27 inch monitor. My secondary card is connected to my 24 inch monitor, and my 42 inch LCD TV. All 3 monitors are working as extended displays.

 

[k1114]

My comment was just a correction to i7baby.

What connection/card is each monitor in?