New GPU setup help

[mmmerlin]

Long time miner, long time reader of this forum, first time posting here hence posting in the n00b section and not mining support - mods you can move if you like.

I used to have 2x6950 rig, just swapped one of the 6950s for a 7950 and am having some problems getting it running right.

Problems are as follows: when all 3 monitors are plugged into the old 6950 the new card appears as "Disabled Adapter" in Catalyst Control Centre and is therefore automatically down-clocked to 500MHz and hashrate drops to ~250MH/s. I can get around this by connecting a monitor to it so that it appears as an "Enabled Adapter" but this is not ideal as it means that I need to run the memory at a more reasonable speed in order to avoid visual artefacts.

I have been in the registry and disabled ULPS for the card but this didn't fix the "disabling" of the card, the only way I can find to get around this is to connect a screen to the card. I didn't have to do this with my old dual 6950 setup so this is quite frustrating. I have updated CCC which might be causing the problem, but I had to do this to get the new card seen by the system at all so I don't think a rollback will help.

I'm sure other people have had this problem but couldn't find anything after quite a bit of googling so I thought I would just admit defeat and ask for some help!


System details are:
OS = Win7x64
Miner = GUIminer (using OpenCL)
Display Driver = 9.012
OpenCL(tm) Driver ver. 10.0.1084.4
Catalyst Control Center ver = 13.1 (2012.1219.1520.27485)

If there's any other relevant information I've forgotten then please ask!

PS Just noticed that even when running the new 7950 with stock settings (core clock and mem) that I am a) still getting visual artefacts on the screen connected to that card and b) GPU-Z shows that it is is spending some time at 880MHz and some at 500MHz so av. hashrate is only ~350. (880MHz is its stock clock rate as it is a VTX3D X-edition card, and 500MHz is it's idle/disabled clock rate).

Any help with any of these problems would be greatly appreciated!

Edit: 500MHz is not the idle state clock speed, that's 300MH so I have no idea why it's cycling between 880 and 500MHz.

Edit 2: Also, what overclocking utility would people recommend? I used to use Sapphire Trixx as the 6950 is a Sapphire card, but for the new card, as soon as I close Trixx it forgets the fan profile I created and the fan speed drops so my guess is it isn't able to write to the card. And recommendations on this as well?

[mmmerlin]

Here is a link to see the GPU-Z graphs showing the core clock going up and down:

http://gpuz.techpowerup.com/13/03/08/c3h.png

Have now tried connecting all three monitors to it and that doesn't help keep the core clock stable either.

[mmmerlin]

I probably also mention that the temps seem fine - this downclocking / throttling seems to be happening at 70C which I would normally consider a perfectly reasonable temperature. (And isn't happening on the other card.) Also, the effect is seem whether the other card is running or not.

[mmmerlin]

Bump? 

[vm1990]

as far as im aware you cant mix and match ATI cards without having a screen or dummy plug on the 2nd card you could always try making your own dummy plug with a DVI to VGA adapter but with the 2 cards being from different series of card its the only way i know of to get it to work the way you want 

[mmmerlin]

as far as im aware you cant mix and match ATI cards without having a screen or dummy plug on the 2nd card you could always try making your own dummy plug with a DVI to VGA adapter but with the 2 cards being from different series of card its the only way i know of to get it to work the way you want 

That's great, thank you! Just knowing it's not me being silly and this being the only known work around is great as I now know it can't really be improved upon.

It may be worth noting though that a real screen can be used temporarily, so you plug it, the card wakes up, and will then stay awake/enabled until the next reboot. This means you can use a real screen and don't have to trick it with some sort of active adapter.

[vm1990]

yes a real screen does the same thing as a dummy plug all a dummy plug does is basicly lie to the 2nd graphics card telling it theres a screen attached when there isnt its just 2 connections on the vga port connected to make a loop which make the card think theres a real screen attached