Tagan BZ700 Piperock Issue

I have the following PSU - Tagan BZ700 Piperock - http://www.newegg.com/Product/Prod [...] 6817814015 nad following issue with it:

This particular PSU is a bit strange as it comes with four PCI-E sockets (to connect with PCI-E cables) but only with two of such cables (1 x 6Pin, 1 x 6+2Pin). The next model of Tagan BZ800 comes already with four cables.

I have Asus Geforce 9800GTX TOP on board which requires two 1x6Pin power cables. When connecting the Geforce with those two cables directly to the PSU (1x6+2PIN is detachable so it can be connected as 1x6PIN as well) - I get every time Nvidia warning while starting OS that the Geforce has not enough power supplied to it.

While connecting the 9800gtx with only one of the cables and another through a PCI-E to molex connector it works just fine - and it is no matter which cable I connect - the 1x6PIn on the 1x6+2PIN - it works with both separately but the won't work together. I tried almost every possibility while connecting the cables to the slots on the PSU - with no success.

Hence my questions:

1. Can the 1x6+2PIN cannot be connected to the 9800gtx as the 1x6PIN? Wont it work together with another cable connected in the same time?
2. Is it something wrong with my PSU? Or am I doing something not right?
3. Can this issue be occuring with freezes I experience while idle and load in games - no error messages, simple freeze - I dont know what is triggering these freezes - CPU, RAM or the PSU?
4. Another minor issue with this PSU - seems to be common - while under load in specific games the PSU gives a lot of squak sounds out of itself.

Any suggestions will be welcomed. Thx

When I connect only one of the PCI-E cable and a PCI-E to molex connector it works in every slot on the PSU - so it seems all of them are operational (at least with one cable connected to it). And yes I tried all the combinations - there are two rows of the PCI-E connectors (4 connectors together) on the PSU marked as row A and B - so I tried: AA, BB, AB, BA - with no result;/

Especially because of the squealing and freezes, I'd suspect that PSU.