Is there any Software for undervolting on a Haswell-based platform?
From a bit more than a month ago, I have these two new Hardware pieces:
Motherboard: Supermicro X10SAT
Processor: Xeon E3-1245 V3
As I expect that the first guy that will Post in this Thread will begin his sentence with something like "why did you purchased these Server parts in the first place?", I will say that it was because I wanted to have VT-d support for IOMMU virtualization. Processor couldn't be from K-series as Intel disables VT-d on those, and in that case, the Xeon had better features and lower price than the near identical Core i7 4770. The Motherboard choice was because in order to have VT-d support from Chipset too (Through this is not mandatory, but I wanted to have full platform support for VT-d), I had to use either a Q87 or C226 Chipset, and no enthusiast-class Motherboards uses those, so I preferred to get a true Server Motherboard.
I suppose that for anyone that knows how Supermicro BIOSes usually are, you can expect absolutely NO option to run your Hardware out-of-spec, so I can't touch anything there. While I didn't expected to overclock it, I was intending to be able to undervolt to reduce power consumption and temperatures. Actually, temperatures are running much higher that I initially through - Processor temperature already reached 100?C with thermal throttling kicking in during one occation (Windows XP installation in a VM), thanks to the crappy stock cooling and 30-35?C+ ambient temperatures that we're having here due to a powerful summer heat wave. I have turbo disabled and later I also disabled Hyper Threading, as there is no other thing I can do to keep temperatures under control without spending money on a bigger Heatsink, which is not what I want to do, and can't afford neither. Delidding is too risky for a brand new 300 U$D Processor that I can't replace if I screw it.
Technically, Haswell being a mobile-oriented architecture, seems to scale extremely well when going down, according to this and this, reason why at the stock 3.4 GHz I could still chop down power consumption, and thus heat generated, by a whole 1/3, even more if I was capable of underclocking too because at 3.4 GHz is way overkill for my current needs.
However, there is a problem: As I can't change Multiplier or Voltage from BIOS, I'm looking for a Software based tool that allows me to do what the BIOS does not. I have used such tools on AMD based platforms from more than 6 years ago (Central Brain Identifier for an Athlon 64 Venice, K10stat for an Athlon II X4), which were quite easy to use due to the fact that everything is unlocked for going down as part of the power saving features, however, there doesn't seem to be anything similar for Haswell.
Is there any sort of Software available to do what I want for Haswell? As much info as I was able to get, Intel XTU (Extreme Tuning Utility) may work, but it is Windows-only and I'm currently using Linux, plus according to documentation it only works on Intel based Motherboards with Z87 Chipset, but otherwise everything else looks rather dull.
