T520 Bios update cripples 2720QM cpu

T400/410/420 and T500/510/520 series specific matters only
Post Reply
Message
Author
Mike350
Posts: 5
Joined: Tue Mar 29, 2011 10:56 pm
Location: La Grange, IL

T520 Bios update cripples 2720QM cpu

#1 Post by Mike350 » Tue May 24, 2011 5:53 pm

After I updated T520 to BIOS version 1.25, the Core i7 2720QM processor would no longer use the Turbo Boost Technology to throttle individual cores above 2.2GHz! Previously the cores would throttle up to 3.3GHz, depending on the application, temperature, power management settings, etc.

On a hunch, I reverted back to the previous BIOS (1.22) and the processor again throttles up to 3.3GHz.

Clearly there is problem with the 1.25 BIOS that cripples the processor. Hopefully Lenovo will address this issue in next BIOS update, but for now I recommend people stay away from version 1.25.

If you want to verify this for yourself, first make sure you set the System Performance setting to "Maximum Turbo" for AC and/or battery power (I believe that is the default setting for AC) in the Lenovo Power Manager. Then you can run CPU-Z to view the instantaneous processor speeds, and see the speed change under various loads. Under AC power with Maximum Turbo set, the CPU should be able to throttle up to 3.3GHz. To place the CPU under maximum load for testing, you can use Prime95.

Can anybody with a different processor in their T520 also verify that the 1.25 BIOS cripples the processor? I'd expect that Turbo Boost is disabled for any processor with that BIOS, but I'd like to be sure. Lenovo still hasn't posted an update that corrects the problem.

Mike

ausmike
Senior Member
Senior Member
Posts: 976
Joined: Tue Oct 27, 2009 11:16 am
Location: ~ 3Million Mile Club Member~~

Re: T520 Bios update cripples 2720QM cpu

#2 Post by ausmike » Tue May 24, 2011 9:32 pm

Mike350 wrote:After I updated T520 to BIOS version 1.25, the Core i7 2720QM processor would no longer use the Turbo Boost Technology to throttle individual cores above 2.2GHz! Previously the cores would throttle up to 3.3GHz, depending on the application, temperature, power management settings, etc...............
Mike
Thanks MIKE !!!
wow < :twisted: :evil: :arrow: Lenovo Tech Support > #@$^#^#*#,, GRRR!!
nOW i KNOW why !!


I will be checking on Diff machine (w series)soon > pity they all with QM i7s > sorry
Work: None - Retired ! Yipee!! ~~Older/Hm use:Asus Zenbook i7FHD~~ w701ds CTO;W520cto;T61P-IPSmodels; T43P,...&700Tstill going strong!! DEC Alpha Series OS: Win7x64; OSX; SuSe Linux; RedHat~~

Post Reply
  • Similar Topics
    Replies
    Views
    Last post

Return to “ThinkPad T400/410/420 and T500/510/520 Series”

Who is online

Users browsing this forum: No registered users and 7 guests