WMP54G hardware revision
How can i check my hardware revision/ where can i download windows 7 64-bit drivers for this card?
Drivers for any 64 bit version of Windows can be a problem to find. For version number of your example first read the packaging carefully and look at the disc which came with it. The supplied driver or installation notes may contain the version number. If there is no 64 driver on the Linksys site you might try to work out which chipset is used and see if there's a generic 64 driver for that -- widen your chances a bit.