Compatibility Question re: Wacom and Windows 7 and Dell Precision Tower


I am about to replace my old Wacom tablet and pen that are no longer supported. Although it worked just fine with my old Windows 7 pro (different Dell computer) , when I replaced it with the new dell computer it no longer works. My new system is a Dell Precision Tower 3420. In doing some research I have read that other artists are having difficulty using wacom tablets with Microsoft and / or Dell systems. I tried out some strategies I found in articles, talked to Dell support and Microsoft support without success. I am concerned about buying another tablet until I know better what works for others. Thanks for any help you can offer.