Celeron L2 cache failed?

[Chakoro]

I have a Celeron 1700 which is performing poorly on the CPU-intensive SETI program (roughly 9 hours per work unit).

The motherboard drivers CD includes Gigabyte's Mainboard DMI viewer, which shows that the L2 cache 'maximum size' is 128K, but the 'installed size' is zero.

Has the cache failed, or was it never there, or what?

Gigabyte GA-8SDX, 384 MB PC133, XP Home SP1
more detailed configuration by Sisoft Sandra at

http://home.austarnet.com.au/davekimble/sandra.9nov2003.txt

No cache-enabling options in the BIOS.

 

[SYAR2003]

If you download tweak-xp from totalidea
you can set it with that.

Or do it yourself in registry .

start - run - regedit
Advance down to the following registry key: HKLM\System\CurrentControlSet\Control\Session Manager\Memory Management
In this key, double-click on the SecondLevelDataCache Change from Hex to Decimal, change the number in the data field to reflect your processor's L2 cache size in KB (128 etc.)
Close the regedit, and reboot to implement the change.

SYAR

 

[Chakoro]

Thanks SYAR, I tried that the RegEdit way.

SecondLevelDataCache now reads:
REG_DW 0x00000080 (128)
but DMI Viewer shows the 'maximum size' doubled to 256K and the 'installed size' still at zero.
It then stops:
hDevice=ffffffff
encountered a problem, unsaved data may be lost.

Gulp!
XP is still running fine though.
What next?

 

[SYAR2003]

I searched internet found

http://www.winguides.com/registry/display.php/116/

Seems we did it right .
Could be that the dmi viewer cheats.
What was the L2 value before you changed it

SYAR

 

[Chakoro]

SecondLevelDataCache was originally set to zero.

At winguides.com it does say this fix is for larger than 256K of cache, which doesn't apply, and that it is for external rather than internal (on CPU).
Other sources say some of these reporting tools cheat on the external/internal description.

Winguides also says changing the registry is dangerous.
How true. I downloaded Tweak-XP and tried that, and straight after rebooting I got endless:
Windows delayed write failed - the data has been lost.

All the previous System Restore points failed to reload.
Had to reload XP.
Now SecondLevelDataCache is back to zero
and we are functioning again.

AIDA32 diagnostic tools has been recommended, so I am downloading that.
Other ideas still much appreciated.

 

[Chakoro]

I see that TechnoBabble.com suggests that a SecondLevelDataCache of zero means 'auto detect' and that the special settings described above are only for really large caches - 512K+.

Sisoft Sandra 2004 includes a Memory-Cache benchmark test and my performance matches that expected for its spec,
so I suppose the answer is that there is nothing wrong with the L2 cache.

End of thread. )

 

[ceh4702]

Is the Cache turned on in the BIOS? It can be turned off in the BIOS sometimes.

If you do not like my post feel free to point out your opinion or my errors.

 

[Hainley]

Uhm...maybe I'm behind on my reading, etc....last I heard the Celeron did not have L2 Cache on it. Am I behind the times? If so, let me know!

 

[Chakoro]

ceh4702 - I agree it can be enabled/disabled in some BIOSs, but not in this one. I can't imagine why you might want to switch it off.

Hainley - I think Celerons have been designed to a number of different plans over the years. The P4-based 1700 MHz is designated Williamette-128, and has 20K of L1 cache (called internal) and 128K of L2 cache, called 'external' - even though it lives inside the CPU capsule.

At least that's my understanding based on what I've learned in the last few days.