|I installed a SDram module backwards in a ram slot once, and only once - there were data cables in the way and the lighting was not good - I was at another person's place. Like you, when I booted the computer, I immediately heard something fry, saw smoke, and smelled something like burning plastic only worse. I unplugged the computer as soon as I could.|
I can tell you that
- the ram slot the module was backwards in is fried and can never be used again.
- the ram module that was backwards is fried and can never work again - don't install it in anything - throw it away.
You will see physical damage on both the module contact edge and in the ram slot.
Unplug the computer/power supply.
Take a close look at the ram slot you had the backwards module in, using good lighting .
You will probably see what I saw - black carbon deposits, and places where the plastic had melted, possibly bridging contacts on one side of the slot, and damage to some of the metal contacts in the slot.
This worked for me but there's no guarantee it will work for you......
What I did is clean up all the black carbon deposits and scrape away all melted plastic that bridged two or more contacts in the ram slot.
When I installed good ram in the other two ram slots, plugged the AC back into the compter, and tried booting, the mboard worked fine.
If that doesn't work you have fried the mboard.
It sounds like you're getting a pattern of beeps that indicate no ram is installed, or a ram problem.
E.g. for an Award bios or a bios based on one, that's often a beep of about a half second, silence for a half second, a beep of about a half second, silence for a half second, continuously.
If you're fortunate that should go away once you've cleaned up the ram slot.