w550s switchable graphics

[meeotch]

Is there any way to determine, and ideally control, which of the graphics chips the w550s is using? My old W500 had a switch graphics option right on the power widget, but I can't seem to find one on my new W550s. Sometimes, it gets really laggy, though task manager is showing low CPU usage, and I suspect it's a graphics thing. Often, it feels like going onto battery power and back to AC will leave it in a laggy mode. (My W500 had a similar problem - even though it claimed to be running on the discrete graphics after plugging it back in, it would be laggy until rebooted.)

[brchan]

The BIOS should have an option of controlling which gpu to use: Integrated | discrete | optimus (switching)

Nvidia control panel should also allow you to choose between which gpu to use.

Sounds like the problem is more of a driver issue. You could try updating/rollingback the gpu drivers. If you choose integrated or discrete in the bios, you will want to uninstall all video drivers, then install the driver for the gpu you set.

[hhhd1]

Sometimes, it gets really laggy, though task manager is showing low CPU usage, and I suspect it's a graphics thing.

Task manager shows CPU usage differently in windows 8 and above.

It could show CPU usage of 30% while actually the CPU is throttled back to its lowest frequency and running with actual CPU usage of 100%

go to the details tab in the task manager, and see if any processes is using 25% usage, and see the 'system idle process'

Actual CPU usage = 100 - the usage of 'system idle process'

[meeotch]

Thanks for the replies. Good info about the task manager - I was wondering where they hid the "old school" view. (I'm new to Windows 10, having been on 7 forever.)

As far as the NVidia control panel: there's a "preferred graphics processor" option, but as far as I can tell, no indication about which one is actually in use. Maybe I'm missing it? I'd hoped that the "Auto" setting would do the appropriate thing, since opening the NVidia control panel, selecting a GPU, and hitting Apply involves several 5-10 second waits while the NVidia interface hangs and thinks about things.

You were right about the CPU, though... I checked out the Performance tab of the task manager, and noticed that my CPU was stuck at 0.78GHz. Switching power schemes had no effect, and I was forced to reboot to get the CPU up to full speed again. Is this a known problem? Is there a workaround?

[hhhd1]

I checked out the Performance tab of the task manager, and noticed that my CPU was stuck at 0.78GHz. Switching power schemes had no effect, and I was forced to reboot to get the CPU up to full speed again. Is this a known problem? Is there a workaround?

There is some throttling issues in the w550s, you can google "w550s throttling issues", and see if there is any work around it.

There is a 3rd party tool called "Throttle Stop", you might want to give it a try, assumimg the temperatures are not too high.

(I have no first hand experience with the w550s)

[Ibthink]

W550s does not have any thermal throttle issues, if you are running all the current driver versions.

The only thing important is to disable the Intelligent Cooling setting in the Lenovo Setting app, since this messes with the CPU speed slightly.

The BIOS should have an option of controlling which gpu to use: Integrated | discrete | optimus (switching)

Not on any of the newer models. The Optimus implementation has been changed with the Tx40 line.

[meeotch]

I don't think it was thermal throttling - more like the CPU being pegged to its lowest state. Googling turned up a zillion references to the problem, across most of the lenovo lines, most of which ended with "bios update fixes it", or "unfixed". Nothing w550s specific, though.

I'm fairly certain that it happened when resuming from a closed lid at least once (i.e., not just when going to battery and back). I did update everything through System Update, and noticed a couple of power-related things in there, currently waiting to see if the problem recurs.

The BIOS should have an option of controlling which gpu to use: Integrated | discrete | optimus (switching)

Not on any of the newer models. The Optimus implementation has been changed with the Tx40 line.

I still would really like some way of seeing the current state of the GPU selection, and ideally forcing it to one or the other without going through a slew of menus. I'm not sure why it doesn't exist... Is the machine supposed to be smart enough to switch "on the fly"? (I.e., seamlessly, without restarting programs?) On my old W500, the switch forced a change in the windows color scheme (dialing down compositing effects, I think), and usually required restarting graphics-accelerated apps.

[hhhd1]

I read about w550s throttling issues some time ago at http://forum.notebookreview.com , I suppose those should be fixed if you are running the most recent BIOS and drivers.

Also, make sure you are running in either "high performance" or "balanced" power state.

[meeotch]

Yep - everything is up to date. And I've been through the power settings with a fairly fine-toothed comb.

Unfortunately, it happened again last night. The sequence was: 1) shut lid while on power, 2) unplug, 3) take the subway home, 4) open the lid while still unplugged. At that point, it was pegged to 0.78GHz, and nothing could shake it loose: not switching power schemes, nor turning on/off any of the associated settings, nor plugging it in, nor any combination of those with closing & opening the lid. I did notice that open lid open, it briefly went up to 1.25GHz before clamping back down to 0.78GHz.

The the weirdest part: after finally giving up and just trying to use the machine in its slow-as-molasses state b/c I didn't feel like rebooting, it eventually snapped out of it on its own. Took at good 15-20min, though, during which period it was almost useless for even simple stuff like web browsing.

Oh Lenovo, what happened to you? Between this and the needlessly reshuffled keyboard, I'm nearly convinced to just send the thing back.

[SafeHarbor]

Hi,

Here's an interesting posting on Lenovo forum:

https://forums.lenovo.com/t5/ThinkPad-P ... -p/2223149

I've watched mine throttle back, as indicated in Task Manager, quit frequently. My power plan is currently set on the goofy aircraft sensing plan in Lenovo settings. (I'm going to enable a "Balanced" power plan and/or uninstall Active Protection, since I don't know what it may be protecting and it sounds like it's supplying said goofy lap sensing.)

[meeotch]

Thanks for the link - that is interesting. As far as I know, Active Protection is/was a thing related to old school spinning rust drives. Now that we're all using ssd's, I don't know what it's "actively protecting" anymore.

Just happened to me again, btw... This time, the sequence was: 1) using the laptop on battery, speed was fine. 2) closed the lid. 3) came home, plugged it in, opened the lid. 4) stuck at 0.78GHz. 5) again, after about 10min or so, it stopped throttling.

[SafeHarbor]

Hi - I read somewhere that the Active Protection sensors are powering the cooler-lap mode (intelligent cooling?). Why not set it to hibernate when you close the lid? I've never been confident about leaving one sleeping during transport.