Enabling a second gfx?

[pindis]

Hi guys I have a 6850 and a 5770.

Atm the 5770 runs in the 16x pci port while the 6850 runs in 4x. I have reinstalled drivers to 11.5 and sdk to 2.4. But I'm yet to see my 6850 pop up in guiminer

When i go to catalyst I and watch under information, it says it's there, but disabled.

I tried searching a bit, and didn't find anything. So I hope there's a gentle soul here that would help me our, will even donate 0.5 btc

[Sonata]

You need to trick Windows into thinking that you have a monitor plugged into your other card.  Windows requires at least one display to be plugged into a card before it turns on/activates itself.  You can solve this by plugging in a monitor, starting GUIMiner and start mining, then unplugging the monitor, or just create a dummy VGA plug, which does the same thing, except you don't have to keep unplugging monitors. (http://soerennielsen.dk/mod/VGAdummy/index_en.php)

[pindis]

You need to trick Windows into thinking that you have a monitor plugged into your other card.  Windows requires at least one display to be plugged into a card before it turns on/activates itself.  You can solve this by plugging in a monitor, starting GUIMiner and start mining, then unplugging the monitor, or just create a dummy VGA plug, which does the same thing, except you don't have to keep unplugging monitors. (http://soerennielsen.dk/mod/VGAdummy/index_en.php)

Thanks alot buddy!

EDIT: donation coming in your way!

[Sonata]

No problem, and thanks for the first donation!

[bobR]

See this thread if you just want to buy a vga dummy plug

http://forum.bitcoin.org/index.php?topic=8325.0

[landshark]

One other thing you might want to know...

When you go to buy the resistors, you will notice that you have a choice of several different wattage ratings.

1/8w, 1/4, 1/2 and so on.

I built mine successfully using 75ohm, 1/4w, 2% tolerance resistors.

So, I know these work with my second 6870 card.

If you can't find these exactly, you might try a different ohm rating such as 68ohm or 100ohm...1/4 or 1/2w rated.

I have read that other people have had success with these combinations.

Tolerance does not seem to be a big factor in choosing a resistor for this purpose... but personally, I wouldn't go higher than 5% just to be safe.

Good luck and happy mining!

[pindis]

One other thing you might want to know...

When you go to buy the resistors, you will notice that you have a choice of several different wattage ratings.

1/8w, 1/4, 1/2 and so on.

I built mine successfully using 75ohm, 1/4w, 2% tolerance resistors.

So, I know these work with my second 6870 card.

If you can't find these exactly, you might try a different ohm rating such as 68ohm or 100ohm...1/4 or 1/2w rated.

I have read that other people have had success with these combinations.

Tolerance does not seem to be a big factor in choosing a resistor for this purpose... but personally, I wouldn't go higher than 5% just to be safe.

Good luck and happy mining!

Thanks for the input, but I don't mind just attaching my HDMI in my screen and deplug it once its started )

[Adeq]

The 5-second VGA Dummy Plug (by zorinaq)
http://blog.zorinaq.com/?e=11