area51tourist

Hi, I've spent a few days trying to sort a problem which you maybe aware of: I own I M18x R2 which used to have two 7970M's in it, and my girlfriend owns a M18x R1 which used to have a pair of 6990M's installed. Last month I decided to upgrade both machines to a single 4GB GTX 780M (one in each) and sell the old cards on! Anyway I sold the 7970's to a friend of mine who owns an R1 and after installing them he could not get the second card to function properly. My initial thought was that he could have damaged the second card so I requested the machine so that I could investigate further. After my initial investigation which was to check that the cards were installed properly I encountered exactly the same thing - the primary card would be identified in the device manager but the secondary card would always report a code 12 error. Catalyst control center would function fine, but would not see the second card so, still in the mindset that the second card could be faulty I removed them and reinstalled them in my M18x R2 and they functioned perfect, which then lead me to believe that maybe his motherboard was faulty, so I refitted his laptop with a pair of 6990M's and they worked perfect. So, THEN finally I decided to fit the 7970's in my girlfriends R1 and the same problem reoccurred - primary OK, secondary code 12. I then concluded that maybe the 7970's were incompatible with the M18x R1 but I hear many tales of M18x R1's running crossfire 7970's so what gives?! I am now thinking that maybe it's the laptops BIOS (A05) which is too new and maybe the old (A04) BIOS would allow the cards to work properly or maybe it's the VBIOS on the 7970's - although both identical and were updated courtesy of support.dell.com I guess the latest revision could 'block' out the cards from running properly on a M18x R1 Any thoughts?