Try to use only one VGA to set up, maybe your Tian needs bios update to use SLi, probably you will need to upgrade forceware for using quadro SLi, as I did similar problem when I used riva turner convert my 6800 ultra into quadro, as 6800 Sli work fine , but as quadro did not work at all . So I remove Sli brigde and one VGA, make all the updates necessary, then enable SLi. Turned off PC, intalled second VGA , them everything ok. So maybe you will have to update : 1 - MB bios , 2 - Forceware for your quadro. Also check if your memories are exactly the same in matched slots (don't forget to use ECC , as when I set up my opteron 940 socket , I used commom ddr and I got only beeps as you got also) .