Overclocking Issues

[ZachHays]

I have a gigabyte GA x58 Ud3r, 12 gb of gskill ddr4, a 120mm AIO, an x5650, and a 650w corsair psu. I have been trying to overclock my cpu for the last month and i have gotten it to 3.66 ghz instead of the 2.66 stock speed. It works perfectly fine for around 30 mins after stress testing and it will play 1 and a half games of R6 siege and then it freezes and shuts down. when i reopen the bios it says that there was a problem with my overclock, could mt north bridge be overheating in that time sapn? its got good vrms and vrm cooling but i never pulled the board cooler off to look at anything because i needed the pc as soon as possible. im also having trouble overclocking my crossfire RX 460 strix 4gb gaming cards, i can add voltage and i can add a pinch of core and memory but after i launch a game they crash, could it be my thermal paste, or just the horrible extruded aluminum heat sinks that amd used for these? i will get water cooling for them eventually but right now its not in the budget at the moment. If anyone has any answers or questions, or you need more info then let me know, ill be checking this post all night tonight my time (7:33pm for me) and tomorrow afternoon and night. Thanks in advance for any answers and if you have questions i will answer them as soon as i can

[ZachHays]

under full load the cpu gets to between 50 and 60C at idle 30c max and the gpus are around 60 to 70C idle 30 to 40C i have the fans turned up all the way

[ZachHays]

i use aida 64 to test my cpu, i was using around 1.3 volts on the core 1.8 on pll amd 1.6 volts on dram