hi forum, after installing a sata hdd on a dell 4600 it seems to put the pc into standby, with the power led on the front of the pc, flashing orange, if I remove the drive it boots to bios as normal, I have tried a known good working cable and a different working sata hdd with same results, thanks in advance!

configuration molex adapter to sata

The story is not totally clear to me, but the first thing I would check is whether the molex-to-SATA power adapter is correctly oriented (i.e. not reversed).

The symptoms you describe might be the result of that power cable adapter being reversed, therefore supplying +12V into the +5V supply to the disk, and blowing the TVS (and especially if the drives have no TVS, then expect other damage) on the drives.

Im using a hitachi deskstar hdd 500gb , I
it seemed there was only one correct way it would attach to the molex and the same only one way orientation to the sata power on the hdd?

With some force, these connectors can be reversed, by mistake. People have reported on here before that they have made exactly that mistake, so this why I said it is one of the things which I would check, if I was in your situation.

I don't have time to "hand hold" you through the troubleshooting, but in summary: If your disk drive(s) cause the PC power supply to shutdown, then the most likely explanation is that the drive(s) have been damaged. Therefore you probably have 2 problems: (a) find out how you caused the damage to the disk drives (supplying the wrong voltage to the drive(s) is the typical cause) and then (b) you need to fix the disk drives, if it is confirmed that they are damaged.

Someone local to you who is familiar with electronics can help with point (a). If you are lucky, perhaps someone else on this forum will have time to guide you, but I will stop here. Good luck!

ok thanks I appreciated the suggestions and will check, the orientation, I do have a couple of sata drives around so if one is damaged I can try another ,regards