It is possible that the version of PCI that the motherboard supports is not the same as the version of PCI that the card requires.
If the PCI version is correct, you might find that by re-arranging the physical order of the PCI cards that you can get it to work (slight possibility).
I have posted before about this incompatability - there are PCI versions 2.0, 2.1 and 2.2 (among many others), and just because a card will physically fit in a socket doesn't mean it will work - as you may have just found.
Check your mobo manual for the exact version of PCI supported and ensure that the replacement card you get is equal to or less than that version.
I have had problems with PCI graphics gards, sound cards and network cards in the past - although I am, like you, using a Belkin 4-port USB 2 card (which I bought about 2 years ago), in my case in a PCI v 2.1 socket, in an 8-year old PC. It is entirely possible that the "same" Belkin card is now at a higher PCI version, though.
Another thing to bear in mind: you can connect USB 1.1 ports on the front panel to a new USB 2 card with the existing cabling, but they won't run at USB 2 speed. You need a complete replacement solution (such as the link Background Noise posted) for this to work.
An alternative is to use a USB 2 extender cable - this simply plugs into the USB port(s) at the back and gives you a port at the other end of the 1 m cable which you can position as you see fit.
Shrugs, what little I know from experience is that 2 cannot interface with 1.1 UNLESS the 2 device has it's OWN psu.
Complete and utter nonsense!
A USB 2
only device that is plugged into a USB 1.1 socket simply won't work, irrespective of its power requirements.
A backwards-compatible USB 2 device that is plugged into a USB 1.1 socket will work fine, but only at 1.1 speed, irrespective of its power requirements.
SD