- Such EVGA 1300 G2 is quite pricey, are there any cheaper alternatives?
- Can 3 Antminer S3 be powered by a single EVGA 1300 G2 without problem?
- When overclocking 3 or 4 Antminer S3, how do you solve the power supply issue with 4 power connections each S3 (since a EVGA 1300 G2 only comes with 6 cables)?
1. yes, see below, but EVGA is good
2. yes, EVGA1300 can power 3 ants at default speed with no problem. It can also power 1 overclocked plus 2 on regular speed or 2 overclocked.
3. EVGA1300 has 8, not 6 connectors. people are sometimes confused because it has 6 cables, but two of these 6 cables have double connectors, so the total is 8 (I have one).
In addition, at least my EVGA came with a jumper dummy already, if you feel uncertain as to how to insert the jumper.
As far as cheaper-corsairCX500 or CX500M is a choice, but you need one for each ant and, since there are only 2 connectors on each, you cannot overclock it (at least overclock without going against Bitmain recs). While using CX500M, PCI-e cord gets pretty warm (42C), some people feel uncomfortable about it.
I use EVGA1300, CX500M and CX750M (this one has 4 connectors, but is a bit overkill in power, unless you want to run 2 ants on it on regular speed only).
Very well, that means I'm now considering the purchase of 3 x Antminer S3 + 1 x EVGA 1300 G2 because I'd need a second PSU for the forth S3 anyway, with negative impact on my ROI estimation. Three S3 on one PSU should do.
Alternatives to 1300G2: very few (like the Seasonic x1250), but I don't think you'll find less pricey PSUs in this class. The 1300G2 is a well-engineered supply; it is worth the money. I have many of them; really the only negative things I could say about 1300G2 are that it is relatively noisy (not as noisy as the miners, though) and that it is only Gold rated, not Platinum. You may want to consider buying 2 smaller PSUs (750W class) that may end up cheaper; each can run 2 S3's.
Without OC, running three S3 on one EVGA1300 means running the PSU at 78.46% capacity, which is a good value. Running two S3 on one EVGA750 means running the PSU at 90.67% capacity, so way beyond the recommended 80%. Just a thought.
If you want to use all 4 power connectors on an S3, you'll have to be creative. I have 8 1300G2's; they all came with 8 separate PCIe cables (6 6+2 pin, and 2 6-pin). I am in Canada, so what's in the box may vary from country to country. If you want to use all 4 power connectors on an S3 then you can only power 2 S3's from what's in the 1300G2 box, or find some quality PCIe splitters.
Splitters are generally fine as long as you keep the power below 200W-250W or so (a stock S3 would see about 175W per blade, or 350W total, so it should be ok to use 2 splitters to power the 4 power connectors); you just need to watch for heat buildup at the connection points (crimps points and friction locks mostly). Sometimes you get a cable with a poor crimp or some resistance on the mating contacts which can sometimes create enough heat to actually melt the cable housing and/or sleeving ... something you really don't want.
YMMV, of course, but I've never had the need to use all 4 power connections on an S3. I've played around with dozens of S3's, and all of them had the same overclocking limits, the same HW errors, and the same average hashrate whether I use 2 connectors or 4. I understand that others have had difference experiences.
Any recommendation on such PCIe splitters?
With three S3 on one EVGA1300 with 8 separate PCIe cables that means I could run two S3 on stock frequency with just 2 cables each, and one S3 overclocked with 4 cables attached. Doesn't seem to be a bad plan neither.
