Can't use WWAN DW5630 in Precision M6800

I put this WWAN card (Dell Wireless 5630 WWAN Mobile Broadband card) to M6800, but the card isn't recognize in Device Manager.  I go to M6800 driver download page, but just only DW5808/5570 driver.  So I go to M6700 section. But in Windows 8.1 OS Driver, it's only DW5560 Driver? Ok, I switch to win 7, download DW5630 Driver and broadband app for M6700. I tried to install but still stuck in warning "This is not a DELL compatible system" (What?). Why DELL didn't have any Driver for support old WWAN? Thanks!