The diode, like the parallel resistors, will also heat up. Either the VRM's heatsink dissipates the heat, or some inline component does. I should have some 6 A diodes though.
I ran several tests yesterday and have reached success. I'll report on it in more detail after I run more extensive tests.
By the way, I calculate the current going into the VRM as 1.03 A. I added a heatsink to the VRM and a larger fan to the CPU's heatsink. I've also added a 25 mm fan to the VRM's heatsink. I did add some 2W parallel resistors to drop 2 V . However, over the course of 6 minutes running, that voltage drop increased to 2.5 V, further heating up the resistors. I recorded 63 C on one of the resistors and decided adding a small fan to the VRM's heatsink is better than having inline components.
@Mike, yes, a switching regulator may be better, however I don't think there is any plug-in, pin-compatible, switching regulator that wouldn't require a PCB redesign. With the original spec, from 5.0 Vin to 3.6 Vout, a linear LDO doesn't even get warm. What I am doing now is an after thought, one I never thought would be doing. I don't think anyone else is going to attempt more than 5 V on one of these SXL2 CPUs.
It does beg the question, though - with a peltier and a large copper socket 370 heatsink, can I get 100 MHz out of an SXL2? And at what voltage? Would going too far over, say 5.5 V, start to irritate the northbridge?
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