80 wire ribbon cable blows PS

[needhelp]

Bought some second parts from the computer market and assembled a computer out of the bits.
Everything went well and worked fine but I had used IDE ribbon cables on the second hand hard drive and after reading an article somewhere on the net, I decided to use the 80 wire ribbon in place of the standard 40 wire type on the old connection.
So thats what I did. I connected the blue end to the motherboard and the black end to the hard drive. (only installed one hard drive) The connector to the motherboard connected with no problem, just pushed easily into the slot but on the hard drive it seemed difficult to connect up and had to use a fair bit of force to push the connector home.
Now everything was connected and I powered it up. Nothing happened, no lights, no fan but after a couple of seconds the power supply started to smell so I disconnected the power and had a look.
When I tested the power supply, it showed no signs of life even though the fuse in the PS seems to be ok.The power supply was dead.
Now I installed another PS and reinstalled the old IDE ribbon cable to the MB and hard drive and it works fine again. So what I want to know is why did this happen. I thought the 80 wire ribbons were backward compatible with the old IDE ribbon connections on both the motherboard and the older hard drives. Why did it kill the PS?
The motherboard is a DFI 845GV-MLV The hard drive is a Maxtor 40GB drive.
The ribbon cable has a stamp on it which says, A54639-002 FOXCONN K, 0552. This didn't bring anything up in Google but there is another number E124936-D Foxconn on the ribbon. This brought up a few things on Google but I couldn't pin anything down as to what went wrong.
Any help appreciated.

[kissfan]

In my experience it is unlikely that the IDE cable caused the problem, I would put it down to it being a bad PSU more than anything else.

IDE cables do not draw any power themselves they are just a signalling device (ie data only).

HTH

Kissfan

[Petef56]

I can't stress enough the importance of purchasing a PSU with short circuit protection.
This way if you hardware is defective, at least you don't blow the PSU.

---pete---

[needhelp]

Originally Posted by Petef56 I can't stress enough the importance of purchasing a PSU with short circuit protection. This way if you hardware is defective, at least you don't blow the PSU.-pete---

I will remember that in future. I still can't figure out why it happened though.