Windows NT 4 and SQL v7.0

Due to slow MS SQL v7.0 databases access performance, we are forced to upgrade RAM and purchase additional CPU to my dual-processor capable SQL Server. The problem is Windows NT4 and SQL v7.0 doesnt automatically recognize the additional CPU and were advise to reinstall NT4 and SQL. If this is the real case, I am hesitant to proceed as my SQL application might not be properly restored from backup and run as before. Any thoughts on the issue and guidelines for the proper way to do this?
James.