Strange throttling problem in The Witcher 2: Assassins of Kings EE

[a_dumb_noob2]

My specs are:

i7-4790k @ 4.0Ghz
16GBs of DDR3 RAM
AMD Radeon R9 390x @ 1080Mhz/1500Mhz (core/vRAM)
ASUS z97 Deluxe USB3.1 motherboard
850W PSU
2x120mm case fans
Thermaltake mid-size tower case

Problem is as stated in the title. There is plenty of cooling and the GPU never seems to hit temps higher than 75 degrees Celsius. That said, there is still throttling occurring (noted in MSI Afterburner) and this results in the frame-rate consistently dropping to mid-30s every time it occurs. It appears to be linked to the CPU since the first core on the CPU drops in utilization every time it occurs as well. I have no idea what's causing this because the GPU and CPU are not even close to their thermal limits (95 degrees on the GPU would cause thermal throttling and the GPU never gets close to that), but throttling seems to be happening regardless. Futhermore, the throttling seems to be linked to certain "trouble spots" in the game. That is to say that it occurs at consistent points in the virtual world and isn't happening randomly. My set-up should be able to max out this game without issue, and it does just that whenever the GPU is running at the proper clock speed, but whenever I find these "trouble spots" in the game, it will drop the clock speed to half its max frequency. Does anyone have any ideas of what might be causing this? And if you know what is the root of the problem, would you know what I can do to fix it, if it's fixable?

Thanks

 

[garyshows]

what psu do you have?

 

[a_dumb_noob2]

I have a corsair CX series modular 850W PSU

 

[garyshows]

Oops, I selected best answer by mistake. I have a corsair CX series modular 850W PSU

i would switch the psu before trying anything else the cx series is a low budget psu not made for gaming at all

 

[a_dumb_noob2]

I see. Well, besides your feeling that the PSU is low budget, would you have any idea what is causing the throttling specifically and if I can confirm the psu is indeed the issue. I'm not going to go out and waste money on another PSU if this one is perfectly fine. If it actually is the issue, that's another story, but I need to have some way to confirm your suspicion other than it just being your feeling that it's the PSU.

 

[garyshows]

I see. Well, besides your feeling that the PSU is low budget, would you have any idea what is causing the throttling specifically and if I can confirm the psu is indeed the issue. I'm not going to go out and waste money on another PSU if this one is perfectly fine. If it actually is the issue, that's another story, but I need to have some way to confirm your suspicion other than it just being your feeling that it's the PSU.

even if its not the psu the cx series dies sooner rather then later i would not have that in a gaming build or any build for that matter what if it dies and takes your other parts with it just a suggestion

 

[a_dumb_noob2]

I understand what you're saying and I realize that a better PSU is definitely out there. But unless I know that this particular problem is caused by the PSU, then I am in no hurry to upgrade. I definitely agree though that it will likely die sooner rather than later but it's really not even a year old so I don't see a point in buying a new part before three years without knowing it's the problem.