Topic: Update Large review of Finksy/J4bbrwock server psus compared to ATXpsu-photos up - page 2. (Read 20978 times)

I've actually bought two boxes like that, if you want a bunch, that's definitely the way to go.  Also if you stalk eBay, they show up on there every once in a while for usually around $75 for a box...

And if you want a SMOKIN deal on some on the fans that MarkAZ showed try this link for them at $5 each - courtesy of Philipma

http://www.amazon.com/gp/product/B00YOC80IO?psc=1&redirect=true&ref_=oh_aui_detailpage_o00_s00

Those are great fans but I prefer these because they are a bit quieter and have a nice high CFM (better than the Scythe) but not as much as the ones you posted.

http://www.amazon.com/gp/product/B00XDXHTFA?psc=1&redirect=true&ref_=oh_aui_detailpage_o06_s00

I'll toss in my 2c, I loved the Scythe's with the S5 - it was my goto fan - but with the S7's and the PSU's, I'm only user higher RPM/SP server-grade fans (like Delta's or Sanyo Denki).  These are the best bang for the buck that I've found lately:

http://amzn.to/1ocmdeX

It's almost 2x the CFM of the Kaze and quite a bit more SP - two of these keep the 4k setup nice and cool, and I use a single one of these on my 2880W PSU's with no problems.  The only downside is that these are definitely louder than the Kaze, and they're also PWM - so you need to mod them slightly as the plug doesn't fit on the 4k boards.  On the 2880W, I pair it with a PWM thermal controller, so it still varies the speed of the fan based on the temp of the PSU - although I think you could probably accomplish much the same thing by making an adapter for the existing fan plugs.

So if you're a bit concerned, give two of these a shot and I think you'll be impressed, especially for the price...

Any way you look at it it just doesn't look good for home miners or bitcoin in general.

Also back to the thread, I finally got my 4k board and PSU set up.  I'm running two S7s and one under clocked SP20 at about 700w off them and I noticed that with the scythe fans on the 2 4k PSUs the PSU still feels hot to the touch.  They haven't thermally shut down on their own, but I'm just wondering if the scythes are enough and I'm just being a worry wart or not.  I love the 4k over the 2880w but I'm sure I'll love them both once I do a fan mod to the pair of 2880 if I ever get off my ass.

What we are seeing is not about good miners.

I think bitmaintech has planned this since last fall.

Around Nov we started to see huge swings in hash rate.

I think looking back at it bitmaintech was setting up multiple farms with s-7s

They tested them and knew they all worked.

We would see hash jump super high for a day or two then drop.

Once January came they fired up the three or four farms they built I think they have a six month one cent power contract.

The goal is grow hash at 10 to 20 percent. From now until the 1/2 ing or to when bitfury starts selling its .1 watt gear.


Simple math shows 1 cent power and .3 watt gear beats 4 cent power and .1 watt gear.

So go forward to April 1 and the diff is 240 or 300 buying the bitfury will not look to good.

This will put bitfury in the spot of trying to sell none profitable gear.

Or bitfury investors may attempt a btc price pump to 700 or so.

As I type bitmaintech is holding more the 24000 coins in one account.

So if bitfury does a price pump bitmaintech will score with those coins.

I have studied the bitmaintech addy and they changed the withdrawals right when
The hash rate took off.
Seems to me we are watching some very big power moves.


Now back to this thread.
I got a shipment from finksy on Thursday .  So I now can do one 2880 and three 2980 units

I have four Avalon6s and one coming on Monday.

I did a fan mod on the second 2980 I own and I am running two 2980's
Rather then one set of dual 2000 = 4000 psu and one 2980
The 2980 is clearly the best method in terms of power efficiency .

I now do 15 amps or 3600 watts that allow me 12.7th and it is pretty quiet setup.

With these difficulty jumps they would have to be some pretty impressive miners and they would have to be very reasonably priced but it's all a vicious cycle.  If they are worthy of buying then so many people would buy them that eventually it will get to the point that the difficulty jumps up to the point that they are no longer profitable.  In the end everything just basically ends up in the same boat.  I hope I'm wrong but that's the way I see things now.

Hehe, don't forget, there will always be the next generation of miners hardware.  PSU will always be needed and you won't needing to upgrade them often.

Thanks I managed find a pair finally, but with this crazy expected difficulty increase I may not be able to put much use to them for very long.

I have some spare IBM 2KW PSU that I'm not using as well as PCI-E cables.  If you're interested, please PM me for a good price.

I don't think S9 works.  At least not according to this post http://www.rcgroups.com/forums/showpost.php?p=19881042&postcount=997 you need to reconnect the pins for the voltage mod.

The external pot on the breakout board will only have effect if the PSU is from a revision that can be adjusted
I personally tested revisions from 6 to 10, and 6 to 8 are working. Can't remember if the S9 worked too.
Clockwise will give more offset from the stock value of 12.2v
Counterclockwise will reduce offset to a point you should reach close to stock value.
Setting the external pot in middle position without touching the internal ones should give you 11.8v undervolt and 12.8v overvolt

I tried plugging them in one at a time to the board and neither of them would power up.  I never get any green lights on the back of the unit where you connect the power cord.  I got an RMA and these babies are getting sent back.  Thank you everybody for your help.

I purchased 32 of these PSUs from a dealer on eBay and they are all REV1-REV4 and they all work fine for me using the dual BB. The only issue I saw was at the highest setting, I was only getting 12.30~.40v. This was resolved by tweaking the internal VR501 pot an 1/8th of a turn to the left. Other than that, I haven't had any issues with my older REV PSUs. Mine all end with an "A" though as J4bberwock has mentioned, so that could also be an issue.

Near where you plug in the power cord, you should see two glass domes there with AC written under one and DC written under the other. Do you see either one (I think AC should light up first) light up when you connect the power cable? If not I would say you have bad PSUs. Out of the 32 I tested, the one bad PSU I did have would power up (green light for AC & DC), but would shut down when placed under load. Both the green light for AC and DC would go out, and the volts would drop down dramatically on the LCD display.

@J4bberwock - Could I have adjusted the external pot on your dual BB to correct the issue of the PSUs only putting out 12.30v? I only ask as I adjusted the small pot on the bottom left of the breakout board, but didn't notice a change in volts on the LCD screen or my multi-meter (I was turning the external pot to the left). As mentioned above, I manually adjusted the pot on the inside as I was afraid to keep turning the external one of the BB.

Yes, that's quite strange they used the exact same PSU and connector but not pin to pin compatible for 2 companies.

Huh, had no idea Delta made these for Intel as well.

mine are rev 7 and 8 both have an A at the end

Thanks J4bberwock.  I'll have to be sure to get the right ones.  I didn't even think that would matter and especially since the breakout board still fit perfectly.  Oh well lesson learned!  Going to try to return these.

good catch  I have rev 7, 8 I can look at them  give me a few min

I just noticed that yours is a DPS2000BB B all of mine are DPS2000BB A

I'll try to find a cheap BB B locally to test.
The only ones I could find with a quick search were 200€ ($220) each.

Edit:

INTEL-ABCEPSU20-2000-WATT-INTERNAL-POWER-SUPPLY-DPS-2000BB-B

It's not made for IBM, so it's very likely that the pinout to turn it on is different on this one.