Seems like your CPU is heating up, try to set the intel turbo boost off

I guess no, can't find anything about it on google. :/

@shadowlck did you change the thermal paste? i think acer's thermal paste job is maybe just shit

Not a Acer user, but I think your GPU or CPU is throttling. Try disable your Intel Turbo Boost. and lower your settings. 860m can't play Far Cry 4 on medium high settings on 900p I believe. try 720p instead.

I did turn off turbo boost, its just the same.
what I noticed thought when the gpu hit 85c, the cpu will downclock and the gpu usage with drop then along the fps will drop. but my cpu temperature are just along 70-80. I think ill send it back to check. Not sure I get a flawed gpu termal pasre or fan.

Just to let you know, Nitro fan kicks in a little late, you need to wait for it to spin
Also, I think by default they are using stock thermal paste, it sucks. So just ask them to use IC Diamond or any other good thermal paste.
Can you try on other game as well ? Cause so far what I know is, 860m is not suitable to play Far Cry 4 on mid high settings. This game is very demanding same like Crysis 3. Watch Dogs and AC is also another example, but mostly it is because ubisoft game is always not optimized
Try lowering your resolution to 720p.

erm, what do u mean wait for the fan to spin, I tried ply that game for like 2 hour just to test it, it just went to this same cycle, gpu hit 85c, then usage drop -gpu temp then drop for abit-gpu temp rise to 85- then repeat the process.
I tried 720p medium setting just now, it did not seem to be change. :-( I starting to worried that either my gpu fan something wrong or the gpu thermal paste problem. because the cpu temp are not so high 70-80.

CPU temperature is lower than GPU is normal, as your game utilize GPU more than CPU. Nitro is using dual fan so they are using different heat pipe, so you can see two different temperature.
Mostly GPU will heat up to 70-80+ degree C when you're playing game, especially high demanding game like Far Cry 4, Crysis 3, BF4 etc etc.
I highly suspect your GPU is throttling. If playing other lower demanding game is still the same, mostly is hardware failure.
Did this happen on the previous driver version ? (before you update to latest nvidia driver)
Send it to the shop back for a 1on1 exchange (if is still within 1 week) or service center to have a check up

I tried older game just now on my steam(dead space2),
the cpu and gpu ranging in a whopping 60-70+c, as I think like what u said that ds2is a much undemanding game. but I bought this laptop to ply latest game, but the gpu will throttle in those latest game. This is just sad.

Well 860m is not high end GPU. It can play latest demanding game, but not in high resolution + high settings. COD AW is okay as it is 2014 game. Some 2014 and up coming 2015 game may not work well.
I think better send it back to have a check. Cause for Nitro to go till so high is quite unusual, cause most user temperature is <85 degree c

I think I try to send it on next monday as now cny. This suck as this laptop are still brand new though

i dont think its a hardware issue, the game is just demanding thats all

but if thr gpu cant handle the heat even in low res setting then how im gonna play game in the future

what is the max temp for gpu and cpu while playing the game? other games?

well for far cry , the gpu as I said throttle on85c then drop abit on the temp then repeat, this result in constant fps drop which make the game unplayable. The cpu is fine after turn off turbo boost, 70-80.

Well problem is the GPU is suspected to throttle. I think new GPU won't have this kind of issue in low settings + reso. 860m is a budget + decent GPU, not entry level also.. So shouldn't be throttling much

Nope I didn't repaste the thermal. Your laptop temperature rise again even you set the Intel turbo boost off?

Hmm that's weird. My Cpu and GPU temp are normal while playing far cry 4 (not legit) even in med high 1080p settings.

Getting myself one set tomorrow.. weee~ hoprfully it wont disappoint me

I think I got the defect product. sign