For 2 x 860 watt psu on Seasonic is only about $40 diff and
2 x 1000 watt EVGA about $40-80 premium platinum over gold.
Average plat 860 watt at .16 kw/hr would save about $35 per year each over gold on 240v and $25 on 115v (Pushing 90-100% load mining)
Hmm, I get different numbers than that. The power cost in your area is a big factor though. Here's how I break it down, see if it makes sense.
For Neptune, average power is 1,950W, so recommended PSUs are 3 x 850W, or 2 x 1,200W. I prefer 2 PSUs, since it cuts down on components, cables, outlets, wiring, etc. For example, I can power 3 Neptune miners with 5 EVGA 1300W G2s, vs needing 8 850/860W PSUs.
On pricing, the EVGA 1300W Gold is currently $161.37, or $322.74 for 2. The Seasonic 860W Platinum is currently $169.99, or $509.97 for 3. A difference of $187.23.
Now, with 3 Cubes on 1 EVGA, or, 2 Cubes on 1 Seasonic, you're getting about the same load of 69-70%. That should be getting something like 90% efficiency on Gold and about 92% on Platinum using 220/240V. On 1,950W, that's 39W difference, x 24 hours, x 30 days = 28.08KW/h. I get between .11c and .12c per KW/h, lets say .115c on average, so that's $3.23 more per month for a Gold PSU, or $38.76 per year.
Divide the difference of $187.23 by $38.76 and it would take around 4 years 10 months for the Gold to use that much more in electricity.
Going with 2 x 1,000W EVGA Platinums would be 90% load, which I wouldn't want to do really...more heat, more component strain, etc. That would cost over $66 more for 2, plus the higher load would bring your efficiency down to around the same as the 1,300W Golds, with maybe 1% better on the Platinum. 1% would be about $19.38 a year in savings, or about 3 years 5 months to use $66 worth of electricity on Gold.
All that said, it's not a ton of money we're talking about here, so some people will just go for the better efficiency regardless of the extra cost. Especially if they are "Carbon terrified", as I like to call it.
Or, as I mentioned above, if you pay a premium for electricity and that extra couple % would save you a lot more money. Still, even at 3x the electric cost on that first example, it would take you around 1 year 7 months to use that much more electricity.
Thanks to notthematrix and teslaman for their earlier posts about how to re-flash my Neptune controller.
I used a recovery SD to flash to RC6. Should I now upgrade to 1.06s?
What is the difference between RC6 and 1.06s? Is RC6 the initial version of the firmware (I seem to remember seeing RC6 when I first got my Neptune, before they came out with 1.00).
Glad it helped.
The list of changes is still on github:
https://github.com/KnCMiner/images/blob/master/Neptune/Changelog but long story short, yes, I would upgrade. There were quite a few bugs fixed, CGMiner updates and some improvements. About the only bug I notice now is that the LCD is messed up. Sometimes the IP address will be off the screen, or in the MH/s spot, or the MH/s will be in the IP spot, lol.