WHoa, partner!
The fact new kits are coming out, should tell you something!!!
I recommend using X79-approved ram only, and suggest 1.5v ram.
Thing is votlage may be the same, but you cannot know if CURRENT draw will be the same. With higher bandwidth on the same frequency, you can basically guarantee that the current pulled by those sticks will be higher than on X58. I cannot say that older ram will be fine, but as I work on my X79 reviews, you can bet I will be asking OEMs what they think.
Ram is so cheap now, if you are buying into X79, and cannot afford new ram, I suggest you re-evaluate your priorities.
LOL you sire are VERY misinformed...
Higher bandwidth is from the faster architecture of the memory controller...and does not make the ram draw any more current than it could from any other DDR3 DIMM in any other motherboard. It has absolutely nothing to do with the memory bandwidth.
please google things before you post them if you are not sure.