LG 27GL850-B HDMI works only at 60hz

B

belictony

Disciple
lokeshv said:
finally bought LG 27GL850, available at very good price on amazon today

https://www.amazon.in/gp/product/B07TD94TQF/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1
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i need some help in figuring out what is the supported modes for HDMI port. i am running a cable from laptop USB C port to monitor HDMI port. Max supported resolution comes to 1440p 60Hz. not able to set to 1440p 120hz.

i am using the below cable
https://www.google.co.in/url?sa=t&r...p/B06XDMKQKJ&usg=AOvVaw2XvneTCOIDc1kj2ijH9f5a


any ideas on what could be the bottleneck?
 
belictony said:
i need some help in figuring out what is the supported modes for HDMI port. i am running a cable from laptop USB C port to monitor HDMI port. Max supported resolution comes to 1440p 60Hz. not able to set to 1440p 120hz.

i am using the below cable
https://www.google.co.in/url?sa=t&rct=j&q=&esrc=s&source=web&cd=&ved=2ahUKEwjUuIDM5-nzAhWfzTgGHWeKBr8QFnoECAoQAQ&url=https://www.amazon.in/USB-C-CableCreation-Thunderbolt-compatible-Cable/dp/B06XDMKQKJ&usg=AOvVaw2XvneTCOIDc1kj2ijH9f5a


any ideas on what could be the bottleneck?
Click to expand...
may be the conversion it self if the problem. I am using dp cable and have used HDMI previously. and 120hz was no issue for me.
 
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As mentioned in the other thread, the HDMI port of LG monitors have the restriction, probably because they don't want to spend extra on a higher-end HDMI module and expect you to use DP.

But my 32GK650F still supports 100 Hz, so that should still be possible with the correct setting. The cable is not the issue.
 
gourav said:
Your cable says 4k@30Hz, meaning it won't do 1440p at over 60Hz. You should look for a cable with 4k@120Hz support.

But also, be mindful of @t3chg33k's reply
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as per the bandwidth chart attached, 4k30hz cable should be able to handle upto 2k 100hz or 2k 85hz or 2k 75hz, maybe the monitor doesnt support 100hz, 85 hz and 75hz mode through HDMI.

is there a way to find out what is the version of the usb c display port in HP Probook 440 G5?. manuals doesnt call out the version
 

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belictony said:
Max supported resolution comes to 1440p 60Hz. not able to set to 1440p 120hz.
Click to expand...
I think it's limited by USB-C bandwidth. USB-C can barely support 1x 1080p_120Hz or 2x 1080p_60Hz. That's equivalent to 1440p60Hz. So it makes sense to your USB-C doesn't go above 1440p 60Hz.

You need thunderbolt for the functionality you are looking for.
 
lockhrt999 said:
You need thunderbolt for the functionality you are looking for.
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If USB-C port supports display, then most likely it's a thunderbolt port.

@belictony can you confirm if your laptop has a plain USB-C port or USB-C thunderbolt port? If you're not aware, then look at the port, there should be a lightning icon beside it if it is a thunderbolt port. Alternatively, you can Google the laptop model number.
 
gourav said:
If USB-C port supports display, then most likely it's a thunderbolt port.

@belictony can you confirm if your laptop has a plain USB-C port or USB-C thunderbolt port? If you're not aware, then look at the port, there should be a lightning icon beside it if it is a thunderbolt port. Alternatively, you can Google the laptop model number.
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it has the 'd' or 'p' icon next to the usb c port. not lightining icon.
 
gourav said:
If USB-C port supports display, then most likely it's a thunderbolt port.
Click to expand...
"Display Port over USB-C" is a different spec compared to Thunderbolt 3. If the type C port has only the DP logo, then it's just DIsplayPort over Type C, not TB3. TB3 includes DP over type C tho.
belictony said:
it has the 'd' or 'p' icon next to the usb c port. not lightining icon.
Click to expand...
yea that is a dp over type C port, not a thunderbolt port. That would be limited by it's USB C speed - if it's 3.1Gen1 or 3.2Gen1 (5Gbps), I don't think it will support 1440p120hz. However, if it is a 3.1Gen2 or 3.2Gen2 (10Gbps), then it should support 1440p120hz
 
belictony said:
as per the bandwidth chart attached, 4k30hz cable should be able to handle upto 2k 100hz or 2k 85hz or 2k 75hz, maybe the monitor doesnt support 100hz, 85 hz and 75hz mode through HDMI.

is there a way to find out what is the version of the usb c display port in HP Probook 440 G5?. manuals doesnt call out the version
Click to expand...
To clear things a bit as per my setup, I have an AMD processor, so the USB-C port doesn't have Thunderbolt. Connecting using a USB-C to DP adapter works fine at 2k@144. I have a USB-C dongle that works well with my tablet and work laptop, but for some reason it does not work with my personal laptop, so I cannot test USB-C to HDMI output.

However, I have connected the laptop to my monitor using the HDMI port (2.0b) and it is limited to 100 Hz at 2K. I have connected it to my TV (HDMI 2.1, 4K@120) using a HDMI 1.4 cable and 4k@30 as well as 2K@120 works fine. In short, the HDMI port on the monitor does not exceed 100 Hz by design. My monitor does not have G-Sync but you need to change the FreeSync mode to Extended from the settings to get 100 Hz.
 
t3chg33k said:
To clear things a bit as per my setup, I have an AMD processor, so the USB-C port doesn't have Thunderbolt. Connecting using a USB-C to DP adapter works fine at 2k@144. I have a USB-C dongle that works well with my tablet and work laptop, but for some reason it does not work with my personal laptop, so I cannot test USB-C to HDMI output.

However, I have connected the laptop to my monitor using the HDMI port (2.0b) and it is limited to 100 Hz at 2K. I have connected it to my TV (HDMI 2.1, 4K@120) using a HDMI 1.4 cable and 4k@30 as well as 2K@120 works fine. In short, the HDMI port on the monitor does not exceed 100 Hz by design. My monitor does not have G-Sync but you need to change the FreeSync mode to Extended from the settings to get 100 Hz.
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I think its the cable.
 
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