Can the AMD Phenom II X4 800 L3 cache be unlocked?

Posted on Wednesday, March 04 2009 @ 20:19 CET by Thomas De Maesschalck
Last week an Asian site discovered the fourth core of some triple-core Phenom II X3 720 and 710 processors can be unlocked, and today VR Zone claims it's also possible to unlock the missing L3 cache of the Phenom II X4 800 series processors. These chips are sold with 4MB L3 cache, but the site heard it's possible to unlock the disabled 2MB L3 cache, to get a total of 6MB L3 cache.

The site got its news from German tech site Planet 3D Now!, which published some screenshots and benchmarks as proof.

However, unlike with the story of the unlocking of the fourth core, the German site has no idea how they did it. They were overclocking and playing with the BIOS when suddenly the disabled 2MB L3 cache came alive. It was definitely not a wrong readout, because the benchmarks show the performance was indeed higher when the extra cache was enabled. They speculate it may be a BIOS bug that enabled the cache, because after doing a CMOS clear the chip could once again access only 4MB of the L3 cache memory.


About the Author

Thomas De Maesschalck

Thomas has been messing with computer since early childhood and firmly believes the Internet is the best thing since sliced bread. Enjoys playing with new tech, is fascinated by science, and passionate about financial markets. When not behind a computer, he can be found with running shoes on or lifting heavy weights in the weight room.



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Re: Can the AMD Phenom II X4 800 L3 cache be unlocked?
by Anonymous on Saturday, March 07 2009 @ 15:10 CET
In Korean Site also discoverd hidden L3 memory 2MB

I'm not good at English but some people said use biostar 790GX motherboard (I didn't find exactly name)

ACC mode on (maybe "Auto" mode)

they found L3 cache memory changes 4MB to 6MB)


Here is about that (but written in Korean)

http://www.parkoz.com/zboard/view.php?id=over_freeboard&page=1&sn1=&divpage=2&sn=off&ss=on&sc=off&select_arrange=headnum&desc=asc&no=8270http://www.parkoz.com/zboard/view.php?id=over_freeboard&page=1&sn1=&divpage=2&sn=off&ss=on&sc=off&select_arrange=headnum&desc=asc&no=8270



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