09-07-2011 02:37 AM
T420 with Core i7-2620M.
Windows 7 Ultimate x64
I discovered last night that the CPU wouldn't go beyond 2.70GHz no matter what I did - Prime95 Torture tests, video encoding, Visual Studio intensive tasks.
Updated Intel AMT Firmware this morning, and the BIOS to 1.33 - these changes have made no difference.
Power manager shows Intel turbo Boost Technology as enabled.
Enabling/Disabling Lenovo Turbo Boost+ has no effect on the issue.
BIOS is set to maximum performance for AC and battery.
These tests are being conducted with the battery in, and AC connected.
Lenovo telephone support just checked a couple of things and then said "we only support 2.7GHz" which I know is not correct from reading other threads like this one: http://forums.lenovo.com/t5/T400-T500-and-newer-T-series/T520-Bios-update-cripples-2720QM-cpu/m-p/44...
Any tips for other things to check or do are more than welcome.
Thanks in advance.
Solved! Go to Solution.
09-07-2011 04:47 AM
09-07-2011 06:19 AM
Also having this problem on an i5-4210m equipped T420. In my case I also have an SSD, an Intel 310 mSATA drive, but have transferred the OS using Rescue and Recovery and thus should have all original drivers as installed.
09-07-2011 08:10 AM - edited 09-07-2011 08:12 AM
This problem is common in a variety of recent Lenovo laptops. Start by making sure that SpeedStep (EIST) is enabled in the bios. If that is Ok and you still have this problem then you should be able to solve this issue using,
Check the Set Multiplier box, adjust that until it shows Turbo, make sure Disable Turbo is not checked, click on the Turn On button and your problem should be solved. After this you might be able to exit ThrottleStop and not need it anymore until next time this bug happens. Other users run ThrottleStop all the time. It's a very efficient program when minimized to the system tray. Be careful when using ThrottleStop on battery power because many laptops are not adequately designed to run a Quad Core Sandy Bridge CPU at full load and full speed when on battery power. Drawing large amounts of energy from a battery is usually not good for its long term health.
09-07-2011 09:36 AM
Thanks for the reply unclewebb - I appreciate it.....
If you read my second post though you can see i've swapped out my ssd for my original hdd, and that turbo boost is working fine on the original hdd - therefore it isn't the bios.
I've used Throttlestop today and it does enable the boost when configured as you describe below.
However I don't believe it to be a good solution, this feature should work just fine without using a third party driver.
I'm going to rebuild the machine from scratch at the weekend and see if I can't get it working that way.
I'm not keen on using throttlestop unless I absolutely have to.
Regardless of all that though - when the boost is enabled - it makes a massive difference to my work compile and build times and general loading of development environments e.t.c so I'm glad about that.....I just have to make it work correctly now
09-07-2011 09:42 AM
09-07-2011 11:12 AM - edited 09-07-2011 11:16 AM
The OP already said it was enabled in Power Manager, and that the only difference is whether essentially the same image is running off the mechanical hard disk or the newer SSD. In my case, note that I already said that I did use Rescue and Recovery to port my image over as well.
In my case, doing a system restore was the only thing that worked well. Before the restore, which I did earlier today and luckily only took minutes, Power Manager was showing Turbo Boost enabled while plugged in, but there was no indication it was actually running. I tried using Throttle Stop just to see how it worked, but it seemed to permanently set the system in turbo mode, resulting in horrible battery run time and the fan always on. (Hence the restore.)
Now that I've restored, it's working. I'm happy, but confused.
09-07-2011 12:52 PM
Correct it's enabled in power manager lucounu,
Thanks for the reply though Colonel, all suggestions are welcome at this stage - I fear I'm going to have to format and start again though.
The image is not the same as the factory disk lucounu, the non working image was a clean install of windows 7, although imo all I should have to install on top of a clean windows install to get this to work are the chipset and base hardware drivers.
I'll give it a go tomorrow night on a spare hdd I think (before I reformat the ssd) and see if it works on just a bare windows install with minimal drivers (and no lenovo power tools e.t.c)
any other thoughts or observations are again, more than welcome
09-07-2011 08:28 PM - edited 09-07-2011 08:31 PM
09-08-2011 04:39 AM - edited 09-08-2011 04:54 AM
Yeah I've tried Windows High perf setting in windows power manager mate - didn't make any difference - thanks though.
I don't have a "minimum cpu" setting in advanced power settings, I did enable all the core parking stuff last night to see if any of that would affect it, the only thing that did permanently scaled the CPU to 2.7, which wasn't really waht I was after.
Whats the exact name of the setting in the advanced power settings that you're talking about - and which setting is it listed under?
edit - I've just checked my power options and I appear to be missing "Maximum Processor State" and "Minimum Processor State" options - can any other T420 owners here confirm they are seeing those options?