HI: I have and "old" (ok, it IS old) Micron Millennia XS (1.7ghz P4) tower desktop. It has been working fine for years (left on continuously), but recently has been found shut off with it power light red instead of green. (Which normally indicates sleep mode.) It stays on anywhere from 2 hours to more than 12 hours. I've never caught it shutting off, so I can't swear it isn't going into sleep mode, but I can't get it to power up without unplugging the unit and plugging it back in and then restarting. (BTW, some power was definitely getting to the mainboard, as the small green LED on the mainboard was lit inside the computer.) Anyway, I deduced it had to be: a) An OS issue (ruled out now), b) Heat Issue, or c) a Power Supply Issue. Having rule out the OS issue, and seriously doubting a heat issue, I decided to try the PS issue (besides it's the easiest to test vs. the heat issue.) So, I went to use a PS from my even older Micron P3 700mhz that was not being used, however it did not have what appeared to be the right connectors, so I grabbed a PS out of a "newer" Dell XPS 3.0ghz P4 I wasn't really using. Here is where it gets weird ... I go to pull out the PS from the Meillenia XS and discover it has the normal 20-pin mainboard connector, but ALSO a 6-pin (auxilliary connector one RED, two ORANGE, three BLACK, labeled "P8"). Now the motherboard also has the standard 4-pin +12v2 connector (two-yellow two-black wires)as well. However, it seems like there was nothing plugged into it, but from my understanding it had to have been or the CPU would not get enough power (or possibly any power). The old power supply does have the +12v2 4-pin connector (and of course the aforementioned 6-pin aux.). The newer PS (from the DELL) does not have the 6-pin connector. So, sorry for the long drawn-out setup, but I guess what I want to know is ... will plugging in the 4-pin +12v2 connector (which I'm pretty sure had to have been connected before) and not having an auxillary (6-pin) connection cause any problems. The motherboard is a D850GB chipset if that helps. Also, IF for some reason that 4-pin +12V2 connector had come out ... would my PC have even powered up, and if so, could that have been the cause of the computer randomly shutting off, and therefore my old PS was fine? Thanks, and again, apologies for the lack of brevity. Best, Tim PS> Is this some kind of hybrid AT/ATX motherboard or something?