How can I tell NT how much secondary cache (L2) is installed?

A. A. NT will try and detect how much L2 cache is installed at startup time however it cannot always tell and will use a default of 256. If you have more you can manually configure NT with your exact amount

1. Start the registry editor (regedit.exe)
2. Move to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management
3. Double click on SecondLevelDataCache
4. Click the decimal base and then enter the amount, e.g. 512 if you have 512K of cache.
5. Click OK
6. Close the registry editor and reboot the machine

The above only applies to processors below the PII, processors at PII or above level will correctly identify the L2 cache size. For more information see Q183063 at http://support.microsoft.com/support/kb/articles/Q183/0/63.ASP.