Seems kinda ubnormal. GL553 is known to be warm under load, but not like this. The most strange you say it was working all fine.
If I were you, I first will worry about thermointerfaces. But I m not experienced user, and problem could be anywhere else.
>temperature of CPU & GPU,within 5 minutes of startup without performing any single task
That's weird. Can you check frequency and CPU load in period when you got 60-65°C CPU/58-60°C GPU? The easiest way is Task Manager. I got 60°C/3600 RPM only in computing tasks, average idle temperature is 45°C CPU/40°C GPU with Turbo Boost enabled. I suggest your already checked that it may be some process loading your CPU, but you do not report it, so, did you check processes? What programs you got in autoload? Launched Steam, for example, can load GPU on idle even when it is on background.
60°C for GPU in idle is to worry about. In this model CPU can worm up GPU even if GPU is disabled. In computing tasks I perform I got disengaged GPU warmed up to 45°C, but not more.
>when i play games there is huge fps drops & screen shattering,the game starts like 60 fps & within few seconds it decreases to 6 fps(sometimes even worse) then it goes up-down-up-down & it results in every games i tested even in the lowest possible settings
What is 85°C? Does it go over 90°C? Check CPU throttling and frequencies (for example, HWInfo64 has special section in it's sensor reports "Core # Thermal Throttling" with results "YES/NO"). In my specimen I got avg 80-85°C with max 88°C for CPU during 3+ hours gameplay, no and no framedrops.
>ROG gaming center shows the GPU memory to 3504 mhz though i am not doing OC
It is absolutely normal, this means GPU memory operates on it's 1752Mhz nominal, with 7008Mhz effective (4x1752Mhz, or 2x3504Mhz) speed. Do not know, what "effective speed" means in details and why it is 4xnominal, but it's normal. Do not be bothered it's coloured red.
>5600 rpm
Cant' be. Maximum auto fan speed is 4800 RPM, if maxed manually with slider, it's 5200 RPM.
