I believe I found the 1st thread that you're refering to. I'm not sure if this one would help.
M2-atx anti-thump suck
Although I'm using the DSATX PSU there may be some inherent similarities. My MB would turn off and then off again until I introduced a small mA relay between the PSU and the MB turn-on connector. Apparently the LV MB's needed a longer turn-on pulse than what was available from the PSU. I'm still a noob but I hope this helps.