I agree there. In fact, there is very little that will push the same load as Prime95.
To me, when I want to declare my overclock stable, I want to stress it beyond any level it will ever see in real use. If it isn't Linpack stable then in my book it just isn't stable. I always use Prime95 to start my testing and once I have a good solid 12hours there I move on the Linpack testing to finalize my OC. There have been times that I never made any changes and it went on to pass, but more often than not I need to change just a few small details.
My whole point is exactly what you brought up. With all these coolers within a few degrees C, I like the extra load Linpack offers to separate them. I have not come across a single heatsink, including the almighty TRUE 120, that could tame my QX9650 @ 4GHz. Only water was able to do that.
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