Laptop screen turns black when screen light turns on after a gap of few minutes of inactivity

[Vincent_Jullie0]

Device:- Hp 15s-DU0094TU

Operating System: Microsoft Windows 10 (64-Bit) | Version:- 21H1

Product Id.- 7NH61PA#ACJ
CPU:- Intel Core i3-8145U

GPU:- Integrated Intel UDH Graphics 620
Age of system:- 1 year 3 months (15 months)

1.

I face a problem with the display of this laptop from the very beginning days.
When I purchased this product its screen frequently turned black even when I would write something in word and so on.
Then I complained and requested for a servicing to HP and they instantly changed the motherdoard of the machine. Afterwards everything was right. 
In the last 2-3 months the black screen issue again came, and specifically the screent turns black when the display light turns on after few minutes of inactivity (for the inactivity the screen light turns off after some seconds), and when the screen turns on, no cursor or anything is visible, and remains black for some seconds to some minutes. 

As a remedy to this problem I performed-

1. Downloaded new drivers for Intel Graphics/ Display adaptor, and also from HP Driver & Software download-centre and installed that to update driver version. 

2. Uninstalled and reinstalled the display adaptor drivers from device manager.

3. Updated the BIOS Firmware from HP website for drivers & softwares download.

-----------------But nothing has changed.

2. 

Rather, when I installed this Intel Graphics Driver Version 30.0.100.9684 to this laptop (See as per the description in the intel site it is completely compatible with tthe CPU and GPU of my device) and nothing got improved, but a new problem- All of the browsers (I prior to this problem used Microsoft Edge and now use Opera) in the machine has become ridiculously slow and lagging after the graphics driver update., and I had to switch off from MS Edge and shift to Opera.
I immediately uninstalled the driver version and installed 27.20.100.8935  in which it was before the 30.0.100.9684, but still the browsers are slow and lagging.

Now please give me a solution to the issues of black screen and slow browser.