Question Laptop won't let external moniter go to 240Hz ?

[tommyjhons]

i have a

ASUS - Vivobook 15.6" Laptop - Intel 10th Gen i7 - 8GB Memory - 1TB+256GB PCIE SSD​

Model:X512JA-211.VBGB
SKU:6449520 and a

Acer XF250Q monitor - - i havce tried almost everything i know of reseting setting, display settings in windows, new hdmi cable, ect i tried it on someone else pc and it seems to run at 240Hz but won't run on my my laptop which doesn't have a DP port.​

 

[bill001g]

Do you know what type of HDMI port the laptop has. It really need hdmi 2.0 to be able to run 1080 at 240.
I could not find your exact laptop on asus site but similar x512 models only have hdmi 1.4.

The older version hdmi 1.4 can only partially do 240 if you set the sample to 4:2:0 rather than the standard 4:4:4.
Not all cards and/or monitors support 4:2:0

Now it could be the rather common issue that the laptop is being a pain and using the setting for the built in display on the external monitor. It is a matter of digging around the display setting to be sure it know you have 2 monitors and they each have the proper setting.

 

[tommyjhons]

yea im using 1 moniter which is the asus one while my laptop one is shut off in setting here is the laptop : https://www.bestbuy.com/site/asus-v...ry-1tb-256gb-pcie-ssd/6449520.p?skuId=6449520 im not sure about the hdmi type

 

[tommyjhons]

i think its HDMI 1.4 my laptops card is Intel(R) Iris(R) Plus Graphics

 

[bill001g]

Before you go to lot of trouble be aware you are not likely be able to see the difference between 120hz and 240hz.
Most times you can only tell if there is a frame counter turned on.

The only people that claim there is a difference are playing shooter games and have the graphics setting set to very low to increase the frame rate. If you play these games is your laptop even capable of running the game that fast.

What I would first try to do is get it to run in dual monitor mode. That way you can see the setting for both devices independently. You should then if you want either close the laptop or turn off the laptop display in the video settings.

Note you likely are going to have to set it to run 4:2:0 which is a very compressed data format. a 1.4 hdmi port does not have the bandwidth to run 240fps at 4:4:4