Regarding the L2 cache registry adjustment in XP... HKLM\System\CurrentControlSet\Control\Session Manager\Memory Management\SecondLevelDataCache I have an older AMD K6-2 processor, 450MHZ with a 512K L2 cache that i'm crunching SETI@Home data with. The SETISpy program was reporting that there was no L2 cache, however after i made the above registry adjustment it reported correctly that there was 512K available. My question is this... the Ars Technica website states that any CPU that is K6-2 or newer does not need the registry adjustment. However, my K6-2 processor has off-die L2 cache, so in theory the registry change IS needed. Does anyone have any input on whether this registry entry is in fact needed on this machine? Am i assuming correctly that even if it is NOT needed, that the registry entry does not hurt anything? Thanks for your input. Jim

See if this helps . L2 Cache Tweakage http://www.subvers.com/technobabble/html/tweaks/access2.htm http://www.tweaktown.com/document.php?dType=guide&dId=145&dPage=6 Use AIDA32 to find L2 cache level . Aida32 is now called EVEREST Home Edition (it's still free). http://www.lavalys.com/index.php?page=products_index EVEREST Home Edition is a freeware1 system information, system diagnostics and benchmarking solution for home PC users, based on the award-winning EVEREST Technology. It offers the world's most accurate system information and diagnostics capabilities, including online features, memory benchmarks, hardware monitoring, and low-level hardware information. The L2, or second-level, cache, is an integral part of your CPU. However, XP is very shoddy at detecting it, so setting it manually is sometimes necessary. It's easy to do, though, you simply have to navigate to RUN>Regedit> HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management\ in the registry and find the value SecondLevelDataCache. You must then adjust it to the value (in kilobytes) of the L2 Cache of your processor. You should be able to find the L2 Cache value of your processor from its manufacturer. NOTE: The L2 Cache of your processor should be entered in Decimal mode.

Johnw - The K6-2 has no L2 cache (on-chip), as mtlieb has indicated - "my K6-2 processor has off-die L2 cache". The 512k cache he's referring to is from the motherboard (chipset). mtlieb - Sorry, but I don't know whether or not setting this value makes any difference, either way. Maybe "Ars Technica" is actually referring to the K6-2+ (as it does have on-chip L2-cache) when they say that K6-2 or newer doesn't need the adjustment, in which case it stands to reason that you would need the adjustment. Regardless, your question is a good one. Good luck.

I appreciate the responses from you folks. I think CLegend is correct, and the article should have stated K6-2+ and greater. http://arstechnica.com/tweak/nt/L2-cache-1.html By default, XP sets the registry key for L2 cache size to zero, which forces the HAL to retrieve the cache size. However, if the L2 cache is off-die like mine then apparently the HAL doesn't see it and XP defaults to a cache size of 256K. I'm going to assume that it doesn't hurt anything to state the actual cache size (512K) and leave the registry change as is. It's just one of those things where you wonder if you've actually slowed your machine rather than helped it, but possibly in a way that isn't readily apparent, know what i mean? Thanks, Jim