I have Win7 64bit and a R9 290X...no problem at all install any of the drivers including the latest.
Clean Install AMD Graphics Drivers
** Windows 7 and Windows 8.1 must be fully updated before attempting to install any AMD driver. All 'critical', 'recommended', and 'optional' (no language packs,etc) updates as well as any Service Packs (SP) must be installed before any attempt to install graphics drivers. If you do not get this message .... keep installing until you do: