Unfortunately what yo uare describing is the exact opposite of what is happening with enaberif's system. He has installed a SINGLE 8800GT and it is not working while I have installed a pair of HD2900XT cards and it IS working. Luckily, my contact with Antec extends pretty far beyond the
PR department so I have quite a bit of information regarding their products outside of what a normal
PR rep would give me.
I monitor numerous forums and I have yet to see this problem with the TPQ 850W mentioned anywhere outside of this thread. There are MANY people who have this power supply working with setups FAR beyond a single 8800GT and there are no reported problems from what I can see. I see no problem here one way or another; from interior quality, rail layout, filtering stages and DC output stages there is nothing in the TPQ that would hold it back from producing its 18A on each of the +12V rails.
You should also be aware that for about a year now (ever since the SPII 450W debacle) Antec has had an in-house PSU testing facility. Much like Corsair, every power supply they begin manufacturing goes through a rigorous test period so the QA at Antec is leaps and bounds beyond what it was a little while ago.
Finally, I would like some concrete proof of these power supplies being failure-prone. I have given up info that shows that they work fine (my review unit was PURCHASED from an etailer) by giving you 3 reviews where it worked for higher-wattage systems the a single 8800GT system. I would also invite you to take a look at the other reviews; most of which were done with systems above the specs of enaberif's system.
Antec.com Are they ALL lying? IMO, there may be a problem with a SMALL QUANTITY of the TPQ series and the people who have those problems are a very minor yet vocal crowd. To assume that the majority of TPQW 850W power supplies have a problem would be a huge error. So far I've got a count of 7 working TPQ 850 PSUs out of 8 customers with the one not working belonging to enaberif. That is far from convincing me that there is a problem with these. Another option could be that whoever is having a problem with this unit is not plugging the modular PCI-E cable into the right modular interface connector. Just a thought....