cancel
Showing results for 
Search instead for 
Did you mean: 

OpenCL

Journeyman III
Journeyman III

CAL cannot find 2nd card on dual hd3870 without monitor attached

Hi,

I have a dual hd3870 machine (crossfire not enabled) running winxp 64 bit. It seems as if the catalyst driver (8.4) will not enable the second card without a monitor attached. calDeviceGetCount is returning 1 with one monitor connected to one of the cards and the other empty. If I connect both cards to monitors Catalyst and CAL both behave as expected (ie both cards appear and calDeviceGetCount returns 2). I managed to get it to work by connecting the second monitor until catalyst enabled the card and then removed it. The device stayed alive for that windows session; however, upon shutdown/restart it disappeared again. I assume it is the autodetect feature, but rather than play tug of war with the driver I figured I would see if anyone else had a similar experience and got it to work permanently. So to sum up, I want 1 monitor with 2 cards enabled without using crossfire.

Thanks in advance
-Jan
Tags (3)
0 Kudos
Reply
3 Replies

CAL cannot find 2nd card on dual hd3870 without monitor attached

Hi Jan,

Unfortunately, the driver currently only enables the card if you do exactly what you did (plug a monitor in during the enabling operation and then you can remove the cable). For the FireStream 9170, the driver will be able to enable the card without a monitor attached.

Now, depending on your monitor, if it has 2 inputs and you normally only use 1 input, this is a trick I used in our labs. I plugged the second card up to the secondary input of the monitor to provide the driver with what it needed.

I haven't tried this myself, but a KVM might do a similar trick (I'm not sure what the KVM sends out on the unselected video port).

Michael.
0 Kudos
Reply
Journeyman III
Journeyman III

CAL cannot find 2nd card on dual hd3870 without monitor attached

I have recently seen a nice trick which should help

 

http://forum.eeeuser.com/viewtopic.php?id=7562

 

 

 

0 Kudos
Reply

CAL cannot find 2nd card on dual hd3870 without monitor attached

Clever trick... :-)

If someone tries this, can they let me know how it works for them?

Michael.
0 Kudos
Reply