I tried increasing the power limit after reading your reply, but it did not worked. From what I have observed, GPU is not getting low power as after I reset the Overdrive my games runs fine , CS-GO specifically and I do not see any frame drops or throttling.
Also , under-clocking only happens during startup and only after 2-3 minutes of logging into windows. If i check overdrive setting right after start-up then they look fine but if I wait for few minutes and then check, I see the upper limits for GPU and Memory clocks beings set to Half of their original values.
Not sure if its steam or CS-GO related.
I have also played around with windows power settings but nothing worked for me. BIOS upgrade is something that I will try next. I also disabled ULPS .
These are the some additional details about my Hardware:
Processor Model : AMD FX(tm)-6300 Six-Core Processor
Logical cores : 6
CPUID : AuthenticAMD family 15, model 2, stepping 0
Display device : AMD Radeon HD 7700 Series on Cape Verde GPU
Display driver : 9.14.10.01183, Crimson 16.3.2
Crimson is slightly older as I was trying different versions, same problem with the latest also.