M17x R2, weird issue with GPUs

Well, i will try to explain whats happening.
I got 2 5870m on my alienware m17xr2, but im unable to set crossfire, because it says it is missing the crossfire cable, which is not, because i have tried with 2 different cables, that are fine.
When i check on the gpuz, appears both cards, with the same bios and all the stuff looks good.
When i try both cards separately, the also run good.
The weird think is, when i try to start the computer with the cards swaped, i got black screen. the computer is unable to start, but if i put them in the original slot, the computer turns on again.
Dunno what is happening, and i want to make sure that the fault is in the cards before purchasing new ones, and not in the mobo.
Thank you.

 

A couple of quick questions

Is it running on BIOS A10?

Is the AC adapter correctly detected in your BIOS?

Which driver version are you running?

 

The bios is A10, the ac adapter works perfect, and the driver version is 12.6

 

Is it in catalyst you cant enable crossfire?
Is your catalyst working properly?

 

Yeah, the catalyst is working properly, i have tried to reinstall several times, and says that the crossfire cable is missing, so is not possible to enable crossfire

 

Maybe the crossfire socket on the card is bad? And i have also experienced switching the cards and the laptop won't boot, just black screen.. maybe you cannot switch the master and slave cards? But when you try it individually they work fine.

Sent from my GT-N7000 using Tapatalk 2

 

How how is decided which card is master and which one is slave? maybe the bios in the cards is bad flashed

 

It is possibly a bad crossfire connector on one of the cards. But just for argument's sake, uninstall Catalyst 12.6 and get rid of all the driver files for your 5870ms in the device manager. Then install the stock Dell drivers and see if Crossfire gets re-enabled. If it does, then update to the latest Catalyst package and see if the crossfire remains active. As far as which card the system decides is master and slave, the card in the left slot is defaulted to the master card and the right slot card (the one on the same side as the DVD drive) is the slave card.

 

Then, why not starting the computer if i swap them? is really weird.

 

Try each card individually in the left (master) slot. Then boot up and see which one gives you the black screen. That will tell you for sure if you have a bad card.

 

As i stated at the begining both cards runs perfect if i run them alone, but only system boots with one of them while both plugged, with the other i only get black screen.

 

OK, now I'm a bit confused. Can you rephrase your last post (I'm a stupid American after all).

 

i wrote it fast, so its a bit confusing:
To clear things up, thats what happens:
Both cards plugged: System starts and recognizes both of them, but im unable to crossfire, because of the missing cable issue.
Only 1 card plugged: System starts, and working, with boths cards
Both cards plugged, but swaped (right to left, and viceversa): System is not starting, all i get is a black screen

 

OK, yeah that is weird. Have you checked the VBIOS of each of your cards to not only make sure they're the same (just in case) but also that all the correct info for each 5870m shows up in GPU-z? Here is a screen shot of what mine looks like (and yours should too):



If the BIOS revision, device ID or ID vendor is x'ed out or in weird symbols, that card's VBIOS could have become corrupted...or the card itself is on it's way to an early grave.

 

Bote bios look like they are ok. ProbAbly one of the crossfire connectors is broken, I think I will try to get another card to try out.

 

Alright. But it's still weird. You should be able to swap them without any issues. Something just doesn't seem right.