TurboBoost failure playing games on AC power

[DKing3]

CPU clock speed drops to sub 1.7Ghz when a game is running in the foreground and the laptop is on AC power. Leave the game in the foreground, unplug from AC using batter, and it appears TurboBoost enables and the PC runs just below 2.4Ghz. The same issue occurs when minimizing the game while plugged in to AC power. Remove AC power and clock speed remains just below 2.4Ghz. I have installed all available windows updates, re-installed updated chipset drivers from acers website.

Screen 1: Game in foreground, AC power, lowered clock

Screen 2: Game in foreground, battery power, appears TurboBoost is enabled

Screen 3: Game minimized (still running), AC power, appears TurboBoost is enabled

Screen 4: Game minimized (still running), batter power, appears TurboBoost is enabled

I have an Acer Aspire R3-471T laptop

Intel Core i5 4210U 1.7Ghz (2.4Ghz)

Windows 10 Pro Technical Preview Build 9926 (I am aware running an unfinished version of windows could be the issue)

The issue was still present prior to updating to the most recent build. It also occurs regardless of game, it even occurs with emulators. Am I missing something here?

Thanks in advance!

[Jose_H_Intel1]

Interesting behavior, I assume it was not happening in Windows* 8.1, correct?

Are you missing any drivers in device manager?

I suggest you report the issue to Microsoft*.

[DKing3]

No issue prior to Windows 10, and device manager looks clean. I did report the issue to Microsoft and the immediate response was that it had to be a driver issue related to Windows 10, which is the response I expected. Was only hoping that I missed something obvious.

[Jose_H_Intel1]

Hopefully this will get fixed before Windows* 10 is officially released.

You may also consider updating your system BIOS

[DKing3]

Reverted back to 8.1. Bios is updated. Still same issue. Does anyone have any ideas? It must be some sort of configuration setting somewhere. I've played with the Intel graphics settings with no luck.

[Jose_H_Intel1]

Please go to Power Options, Advanced Settings. Scroll down to Processor Power Management and expand Maximum Processor State settings. You can use the settings from the image.

[DKing3]

No change. These were the defaults.

[DKing3]

Joe, I would like to update this thread with information posted on Acer. Maybe the Intel minds here can shed some light on what I've found so far...

Update: Changing the brightness while on AC power affects the framerate and performance of gaming. Let me explain...

I have been wondering, due to the complexities of how turbo boost functions, if the power supply provided with these notebooks are sufficient. I wasn't sure how to test this, until now. With AC plugged in, a game running that has no change in scenery or any movement occuring throughout testing, FRAPS running to show framerate, and task manager to show processor clock speed, there is a considerable difference in performance, framerate, and clock speed from lowest brightness to highest brightness settings. I performed the same experiment on battery, with no change performance, framerate, or clock speed. I performed this test on 2 identical notebooks,as well as 2 seperate power supplies (bundled with the notebooks of course), the Acer Aspire R3-471t, running the same game, same OS, same power configuration, etc. with the same results.

Krish, I'm curious if you find the same results. Download and run FRAPS along side your game, and attempt the same experiment above and post your results.

Acer Justin, I would like to attempt this with a different power supply that is compatible with with our notebook. The specs for this notebook calls for a 40w power supply. The one bundled is just that, with 19v 2.1A output. However, the site linked below claims to have the power supply for this notebook, but the specs are different. 65w PSU, with 19v and 3.42A output.

http://www.accessoriesbank.com/ac-power-adapter-for-acer-aspire-r3-471t-54t1-battery-charger-cord.html http://www.accessoriesbank.com/ac-power-adapter-for-acer-aspire-r3-471t-54t1-battery-charger-cord.ht...

Could I risk harming my machine by using a higher wattage PSU with a higher amperage output?

[Jose_H_Intel1]

As long as the voltage of the power supply is the same and the wattage is sufficient, the computer will use the current or wattage it requires.

[Jose_H_Intel1]

Did it help using a higher wattage power supply unit?

[DKing3]

I haven't had the chance to acquire the new PSU yet. I will post test results here as soon as I have them.