3com 1556B combo card laptop will not boot

This is perplexing:-)  Bought a C600 laptop from a associate recently.  Unit originally had a wireless mini pci card in it(Lucent)which he removed and used in another application.  He also formatted the hard drive.  When I received the laptop I also fdisk'd and formated and installed my own operating system(winxp-pro)  All was fine and working great:-).  Wanting a 10-100/56k connection, I decided against the wireless card and purchased a 3cn3ac1556b 10-100/56k mini pci card from 3com and installed it in the C600.  Now it flat-out will NOT boot.  The lights flash on, then off and that's it(lights on laptop).  If I unplug the AC power and run off the battery, the lights flash(no sequence, just off/on/off/on, slowly) and will not stop.  But the laptop does NOT boot.  I have to remove the battery to get the lights to go out.  If i remove the card, everything is fine and normal.

I've been all through the community forum on this one and have seen this problem more than once.  Unfortunately, people tend NOT to post the final solutions or fixes!!!  Hence, I'll try to finish this thread to the end.

To clarify, this laptop will NOT boot up at all.  It will not even make it to bios.  Fact is, the screen doesn't even turn on, the hd doesn't even kick in.  It's like a "hardware lock" or something.  So please don't suggest drivers since I'm not even making it to the operating system.  Nor could it be anything in the bios since we don't even get that far!!!

Some things I've tried:

1.  Replaced the card twice(thinking the 1556B was the problem)

2.  I've seated/reseated this card so many times I have blisters on my fingers!!

3.  Checked all the pins to make sure none are bent/damaged.  They are not.

HELP!!!!

Thanks

Don