Hello ThunderBlade, thanks a lot for posting your inquire at Intel communities.
I’m more than glad to inform you that all 4th generation i3 processors are going to use 35w Thermal Design Power (TDP). This represents the average power, in watts; the processor dissipates when operating at Base Frequency with all cores active under an Intel-defined, high-complexity workload.
The temperature of these processors is going to be around the 66.4 °C. This is what we called the Tcase of the processor.
The following link will allow you to compare all i3 processors. ARK | Compare Intel® Products and this other link will show the i5 processors. There are 2 processors that used 45w and the temperature will be around the 71 °C ARK | Compare Intel® Products
Thank you, very interesting! It seems that the bigger CPUs use a lower clock speed to reach the low TDP. Clever. I'll go for a 4 core i5-4590T, I like the true 4 cores instead of the hyperthreading, and turbo boosting to 3 GHz sounds reasonable... much more doesn't make sense anyway in real world applications because the memory is the bottleneck. But this CPU has quite some cache aswell.
Thanks again, I've ordered the CPU and parts to assemble the new machine... it will be a christmas present.