Windows XP Service Pack 3 Tweaks

Here are some tweaks which were tested in Windows XP Service Pack 3.

Warning: Take extra precaution when altering the registry. Always back up your registry or set a restore point. If you are hesitant, do not proceed.

Note: please disregard equal (=) sign.

1) By default, Windows XP caches both correct and faulty DNS lookups in the DNS cache service. To increase performance, by eliminating the caching of faulty DNS lookups,change the following values from whatever their original values are to hexadecimal value of zero.
Go to:


NegativeCacheTime = REG_DWORD 0x00000000 (0)
NetFailureCacheTime = REG_DWORD 0x00000000 (0)
NegativeSOACacheTime = REG_DWORD 0x00000000 (0)

If these value are not there yet, create them by simply right-clicking then choose New then DWORD Value.

2)Increase the size of the DNS cache

Go to:


Add the following DWORD values by going to Edit > New> DWORD Value.

CacheHashTableBucketSize = set to 1
CacheHashTableSize = set to 384
MaxCacheEntryTtlLimit = set to 64000
MaxSOACacheEntryTtlLimit = set to 301

Enter the numeric values specified by double-clicking and selecting the Decimal option.

3) Enable super prefetch. We thought super prefetching is only available in Windows Vista but it was recently known that it can be enabled in Windows XP SP2 and SP3.

Go to:

Manager\Memory Management\PrefetchParameters

Create and Insert a Dword value with the following details (use exact spelling and capitals):

EnableSuperfetch = REG_DWORD 0x00000001 (1)

Lastly, reboot your computer for the changes to take effect.