So, thanks to your support darksoft, I tried my 4 slot in my New Astro City => Same behavior, not a psu problem.
So...I tried something different because i got a strange behavior since the beginning. The order of games was never respected. Slot 3 starts in position 1 ect...
So I plug a league bowling instead of KOF98, KOF99 or Supersidekick in slot 1 and all went fine ! No more error now.
I have 2x Supersidekick and same behavior...really strange.
Another last thing i can't explain is the bios. I have forced AES, USA and i have JAP MVS, same as 4 slot...I guess I need to get a Universe bios on the slot to get AES mode in the multi.
my firmware revision is 0x0491 and build 0xa512