Windows XP  has many hidden powers disabled by default. One of them is second level cache utilization of CPU. By default windows xp uses 256kB of second level cache memory, but modern CPU have alot of cache (up to 3-4MB). So if you running a powerful CPU on windows xp , you can still boost its performance a little.

How to check how much cache memory you have?

I use a utility called CPU-Z. get this free utility from here cpu-z .

Then check your 2nd level cache memory size.

Now go to RUN-> type “regedit”. (Open registry editor).

Nevigate to key

HKEY_LOCAL_MACHINESYSTEMCurrentControlSetControlSession ManagerMemory Management

look for a dword value called SecondLevelDataCache. its default value is 0 (Which corresponds to 256KB of cache). change it to your cache memory size in KB.

Press OK. and reboot.

Now Windows Xp will use larger cache memory of your CPU.

Note: Don’t try to put a value that is not supported by your CPU.