Hello Rohit338, there is some additional information that I would like to get in order to find out what is causing this clock speed issue.
Would you please provide me this information?
Model number of your processor?
Graphics driver version installed?
Also I would suggest running the Intel Processor Diagnostic Tool to determine if the processor has any issue:
Processor :- Intel(R) Core(TM) i5-3317U CPU @ 1.70GHz, 1701 Mhz, 2 Core(s), 4 Logical Processor(s)
Graphic Driver Version is 10.18.10.3277
One more thing i would to mention that this issue arises only when i either plug or unplug the charger.
i.e if i boot system on battery it will run fine gpu core frequency will reach 1050 mhz but as soon i plug the charger it gets locked at 350 mhz.
only option i find for this is to shutdown and then start or sleep and then resume.as restart doesnt seems to fix the issue.