With the P4 there was a revision to the ATX but not significant since it's also backwards compatible to existing ATX mobo not running the P4. I sincerely believe ATX will be here for the longest time except maybe for few revisions to accomodate new designs. New ATX designs requires total standy capability meaning all power secured to the PSU, including fans and the PSU fan, except for the trickle power to the mobo. Standard ATX goes on standby only with the peripherals but not the fans or the PSU fan itself.