OK guys, I've got it
It's not Gainward nor Asus... A fresh new batch arrived from Leadtek, so I bought a Winfast GTX 480
also because upon researching with the dealer, the cards had the latest BIOS - 70.00.21.00.02.
So tonight when I get home I'll put in my system and "fire it up"
Hopefully my case fans will be enough - 6 x 120 mm & 1 x 140 mm (CM690 case). I'll be back with first thoughts.