I think I nailed it. With luck, I was able to resume the computer with "s2ram -f -a 1", even it's within Xorg. But it still takes a long time to resume, then I found out about my drives hooked on an old IDE extension card stopped working. So I removed the module "pata_hpt37x", and... Wala, 11 seconds ! Now it's only issue is to automated this umount+rmmod and modprobe+mount thing...
