DS3 Question

[UnusualSuspect]

In the stickied guide it says, "Disable all of the following: CPU Enhanced Halt (C1E), CPU Thermal Monitor 2(TM2), CPU EIST Function."

Why is that? I can understand disabling them for working out the temperatures without interference, but surely they'd help keep temperatures lower once the overclock is in place? Right? Or am I missing something?

Only asking because I've kept mine as enabled while overclocking a 2.4GHz to 3GHz, and it doesn't seem to do any harm at all. The idle temperatures are in fact lower than before.

 

[WJA96]

In the stickied guide it says, "Disable all of the following: CPU Enhanced Halt (C1E), CPU Thermal Monitor 2(TM2), CPU EIST Function."

Why is that? I can understand disabling them for working out the temperatures without interference, but surely they'd help keep temperatures lower once the overclock is in place? Right? Or am I missing something?

Only asking because I've kept mine as enabled while overclocking a 2.4GHz to 3GHz, and it doesn't seem to do any harm at all. The idle temperatures are in fact lower than before.

These three things are part of the technology that downclocks the chip when it's not under load and protects it against over-heating.

C1E drops the clock speed to a 6x multiplier when the CPU is idle
EIST cuts the voltage when the CPU is idle
TM1 and TM2 shut down the CPU cleanly when it overheats (85C+ at the cores)

When you overclock, you don't want the motherboard to drop the multiplier or cut the voltage suddenly as it tends to crash the machine. Because you've turned off these technologies TM2 no longer works so you may as well turn that off as well. The chip will still automatically throttle back if it overheats to prevent damage to itself.

Your odd idle temperature situation could be many things, but the most likely one is it's just the CPU/Cooler thermal interface material (TIM) curing. AS5 takes about 200 hours with about 40 high/low temperatures cycles to cure properly and the effect can be noticeable - 4-5C maybe.

With air-cooled systems time of day also has a big effect. Temperatures drop markedly once the heating goes off. There is a wonderful series of posts in the E4300 Overclocking thread where Big.Wayne has his patio doors open at 2am in January (sub-zero outside) so he can he can get his mega-overclock stable. I'm not quite that hard-core myself.