I'm installing my 970A-UD3P into my nzxt phantom 410, but i'm not sure what screws to use. The bags are labled "6-32 screw", "M3*5 Flat", "6-32 *2 screw", and "6-32 screw Hexagon". Which one of them is it?
I think you're wanting to use the M3*5 screws to attach the motherboard to the motherboard tray. The 6-32 Hexagon are for attaching the case cover(s) to the chassis. The remaining 6-32 screws are for your disk drives.
It is usually the 6-32 and that was the size used for my NZXT source 210 non-elite but I had to use the M3 for my Antec GX 500, so if the motherboard standoffs are strange then try the M3.