M-5Y71 vs Core i3-6100U

[themaskofwraith]

core M is 5W CPU while i3-6100U is 15W.
Core M is broadwell while i3 is skylake.

But core M is as fast as i3, sometimes faster than i3.

Not only its faster , it doesnt need a fan.

Now My question is

Does it mean that Intel can make a better CPU with 5W TDP , but choose to make 15W CPU wasting 10W?


Core-M geekbench
https://browser.primatelabs.com/geekbench3/6746805

i3-6100U geekbench
https://browser.primatelabs.com/geekbench3/6741758

 

[Solandri]

The Core M processors have 4MB cache like an i7-U (dual core), not 3MB like a i3 and i5. This makes them faster on short benchmarks.

Their drawback is their low TDP. TDP isn't actually a power rating, it's the amount of cooling Intel says you should pair up with the processor. So a 5W TDP means the CPU attaches to a fan and heatsink which can dissipate 5 Watts of heat. That low rate of heat removal means it's easier for the processor to overheat and throttle. So the Core M performs worse on long benchmarks.

Exactly how much worse depends on the benchmark, its duration, and the room temperature during the test. It's not like the Core i processors which can pretty reliably run at full speed for the entire duration of longer tests. Benchmarks tend to only measure Core M performance for one specific set of conditions and operations. That's why the test results are all over the place, with Core M beating a similar i3 or i5 on some tests, losing on others.

For the Broadwell Core M, there's an additional twist. They will only turbo boost on a single core. Skylake Core M will turbo boost on both cores, which make them more like a miniature i7-U. I am wondering when companies will start to figure this out, and start sticking beefier coolers on a Core M to get i7-like performance more consistently.

 

[rgd1101]

different version of Geekbench , and one is 64bit vs 32bit.

http://www.notebookcheck.net/Intel-Core-M-5Y71-SoC.129324.0.html
"The Core M-5Y71 offers a very wide turbo range from 1.2 - 2.9 GHz. However, the actual frequency is largely limited by the TDP. While the CPU is similar to a Core i7-4500U (Haswell, 15 W) in short benchmarks, its performance will begin to degrade under continuous full load. Accordingly, the main purpose of Broadwell's higher power efficiency is to reduce power consumption instead of improving raw performance."

also other test
http://cpuboss.com/cpus/Intel-Core-i3-6100U-vs-Intel-Core-M-5Y71

 

[themaskofwraith]

its performance will begin to degrade under continuous full load.

But According to notebook check "A very impressive aspect is the fact that the clock does not drop below 1.9 GHz, even after multiple runs of Cinebench "

But i got the answer that i was looking for. Thanks
http://www.notebookcheck.net/Apple-MacBook-12-Early-2015-1-1-GHz-Review.143178.0.html