If it has a Windows 7 license, it'll have a Windows 7 COA on it: [URL] If the COA says Vista its not licensed to run Windows 7. Even if it has the Windows 7 OEM license, it'll be difficult to install without installation media. Microsoft have recently broke the Digital River .isos and instead made a non-functional software recovery tool which deliberately blocks out Dell OEM licenses.
I have a Dell Precision T5400 here, which is still running Vista, 32-bit. I've heard that this machine came with a license for Windows 7 64-bit. Is there any way to confirm this? Do I have to find a copy of the Win7 disks to make use of this license?
Upgrading to Windows 7 x64