Quad crossfire x problem

Hi.My system specs is:MOTHERBOARD-MSI K9A2 PLATINUM 790FX,CPU-5200X2(OVERCLOCKED TO 3.0),
MEMORY-8GB(2X2GB KINGSTON HYPERX 800+2X2GB CRUCIAL BALLISTIK),HD-WD 500GB SATA2,PSU-CHIEFTEC 750W,
VGA CARDS-MSI 3870 512 MB DDR4 OC EDITION+SAPPHIRE 3870 SINGLE SLOT+POWERCOLOR 3870 512 MB DDR4 OC EDITION+
ATI 3870 512 MB DDR4.My operating system is Windows Vista x64 Ultimate Edition and my catalysts' edition now
is 9.1.
I had connected the Msi,Sapphire and Ati Brand vga cards before i buy powercolor
and the triple crossfire x was working fine.After i bought the powercolor 3870 i face many problems
such as i can't enable quad crossfire x,when i connect all the cards the operation system doesn't see
the 2nd pci-ex slot card,the psu doesn't power supplies powercolor card when it is connected as 4th card
but it powersupplies all the cards when it's not connected as the 4th card.Vista also sees all the cards when
i don't have linked them with bridge interconnectors.I have tried again and again to install and uninstall cds'
catalyst drivers and also 9.1 and 9.2 catalyst.I also have tried all possible combinations.I have also tried
to install every single card's drivers separately.I must point that
single cards work properly and until now the 3 of them worked fine linked together.But now i can't enable
2 gpu crossfire actually neither 3 or 4.
Please i'd like to assist me.