I used to think of it as a vacuum cleaner when I owned a dual 1.25, nothing could be done even by replacing the fans in it to quiet it down and it still got hot as hell.
Nope.
I was a bit concerned first as well, but I saw similar differences in the mac fan control thread. I guess its becouse the CPUs are in line, and the rear cooler takes in warmer air.
Could someone with an X5690 in a single-CPU Mac Pro 5,1 do me a favour and tell me what peak temp you hit while running the Prime95 torture test (ideally with hyper-threading enabled)? Thanks!
Could someone with an X5690 in a single-CPU Mac Pro 5,1 do me a favour and tell me what peak temp you hit while running the Prime95 torture test (ideally with hyper-threading enabled)? Thanks!
Nonetheless, Intel gives ≈75˚C. as a 'maximum case temperature' in their table of Xeon thermal characteristics."Intel can't give a specific operational temperature range of an Intel® Xeon® Processor because it will depend on the maximum performance of the heatsink used [and] the way the fans are controlled in a system (which can vary the performance of the heatsink)."
and:"We know from both experience and explicit testing that modern Intel CPUs (at the very least Sandy Bridge, Ivy Bridge, and Haswell) can run at their maximum Turbo Boost frequency all the way up to 100 °C. While there may be a tiny performance difference between a CPU running at 30 °C and one running at 95 °C, our testing has found that the difference is minuscule. In fact, even after running benchmarks dozens of times the difference is so small that it is essentially nonexistent."
concluding:We were very surprised when our testing showed that while the minimum CPU load frequency started to drop as soon as the CPU hit 100 °C, the average CPU frequency didn't drop by more than .1GHz until the CPU was overheating more than 30% of the time. In fact, Intel CPUs are surprisingly good at being able to handle this much heat with such a small reduction in the average frequency.
For the average system, our rule of thumb at Puget Systems is that the CPU should run around 80-85 °C when put under full load for an extended period of time. We have found that this gives the CPU plenty of thermal headroom, does not greatly impact the CPU's lifespan, and keeps the system rock stable without overdoing it on cooling. Lower temperatures are, of course, better (within reason) but if you want a target to aim for, 80-85 °C is what we generally recommend.