CPU cooling: Did I install wrong, or is the box heatsink THAT inadequate?

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1

Long story short, I had a fancy pants Zalman CNPS 9900ALED, USPS turned it into origami, destroying CPU/mobo, and after replacing necessary components, I'm stuck with box cooler (at least I had insurace, just not enough).

Now, I'm trying to get a mild OC from an A8-5600k, but just running stock I'm pushing 74c under prime in place large FFT (GPU idle @ 384MHz), and I have stupid low ambient tems (approx 17c/63f). It is my understanding that Trinity APU's start to throttle around 80c.

It should be noted the CPU fan is at 25% in the BIOS for now, due to noise; in an NZXT Source 210 (rear fan missing 1 fan blade)

2

AMD's stock coolers are junk. intel's are better, but still nothing to brag about. considering that you only have the fan running at 25%, i'd say that 74c at load, is about what should be expected.

3

I bumped the speed to 37.5% (~2400RPM), and I'm leveling off at 70c, but Turbo keeps flucuating rapidly from 3.2 - 3.8GHz. I guess no overclocking. Still a bit of an upgrade from an Athlon II x4 @ 3.25GHz with HD 4200 graphics.

I'm only asking because I don't think I've used the stock cooler before.