What else did you have in your setup cluless other than the 1900XT's? Your 1900XT's should be pulling around 240w....
Not a whole bunch of stuff. Opty 170, OCZ 2x1 DDR500, Raptor 150, one optical, X-Fi, floppy, three 12cm fans, one 8cm. I've OC'ed the GPUs to the max and the CPU to 2.6 on the current PS (mushkin) but the Liberty 620 was unstable with one 1900 at stock clock. I use a good quality Fluke meter to monitor PS voltage to back up Speedfan. With an Evga 6800GS, the Liberty +12V ran at 11.92 to 12.05V. The 1900XT at stock clock pulled it down to 11.80 on the low end and it would spike up to 12.2 occasionally. In comparison, the mushkin is rock solid with two 1900s and OCing them has virtually no effect on the +12V.
What are the specs of your video rig?
Asus A8N32SLI, 4400+, OCZ 2x1 DDR500, X1800XT, two 74GB Raptors in RAID0, two WD400GB YD in RAID1, two opticals, AllInOne front panel fan controller/card reader, three 12cm fans, two 9.2cm fans.
What was happening when you had the PSU hooked up?
Same as in the game box: the 12V ripple was high and the load was enough to bring the 12V way down. Often, I'd start it up and it would make it into the first Windows screen, then it would shut down. It would boot into Windows more reliably if I pulled the two 400GB drives and one optical off, but it would still occasionally latch. No way I could OC the 4400 with the Liberty but with the OCZ PS in, it seems to idle regardless of load. I never managed to get the Liberty to run 3DM06, but with the OCZ in, it's stable running such loads continuously. Enermax looked at the PS and claims it meets specs. No way. Total BS. Thing is, I have talked to two different hardware techs that used to use the 620 in their development systems but after the introduction of the 1900 and 7900 series cards, they have pulled the Liberty out. Then again, I've seen people on this and other forums using the same PS for SLI'd 7900s and XFired 1900s. Must be right on the rivit for that kind of load.