Full Disclosure: Spondoolies Tech (
http://www.spondoolies-tech.com/) sent me an SP20 as part of their “Legendaries Review” promotion (
https://bitcointalk.org/index.php?topic=887807.0) - This is my independent review.
Background: I’ve been involved in home mining in since May of 2011. CPU mined my first block as a curiosity in August of 2010.
Started with a dual AMD 7970 rig in 2011 and grew my farm out from there after learning of the Bitcointalk forums. Have been practically living in the Hardware section ever since, trying to keep up with the shifting landscape of mining hardware suitable for use in North American homes running on standard 115VAC residential circuits.
My farm today: I’m practically at the limits of what my home is able to reasonably power, which gives me an approximate hash rate of about 11THs spread across Bitmain S2’s, Bitmain S3’s, a few A1 clones, and a couple aging 500GHs Bitfury rigs.
The issue I’m presently facing is that many of the 1THs class miners draw ~1KW at the wall, which means I don’t have enough headroom to safely add an S3 onto that circuit.
I can safely run 3 S3’s on a single circuit which net me ~1.32THs, A 1TH class device on a single circuit, or a mix of S3’s and Bitfuries.
Enter the SP20: The SP20 immediately drew my attention because of its amazing ability to undervolt and underclock. The goal was to downclock an SP20 and having it running alongside an S3, with the aim of getting ~1.7THs under 1200W across the two devices.
phillipma1957 has an excellent thread (
https://bitcointalk.org/index.php?topic=872014.0) outlining steps for underclocking your device to ~1.3TH/s here at near 750W that just beats out Bitmain as one of the most efficient and cost-effective, readily available home miners today. I used this guide to configure the system.
My undervolted SP20 running for almost a day now. Shut it down a few times for tweaking and moving it around for pictures.
Getting Started: The initial idea was to replace a very quiet Bitfury rig I have chugging along in our bedroom at 500GHs. It is, for all intents and purposes, whisper quiet and does not appreciably add noise to the ambience of your room, such that it prevents you from going to sleep, or is loud over a television.
Setup: I don’t much like to RTFM, so I stumbled through the usual methods to identify the device.
1) Changed my laptop to a 192.168.1.0/24 address and portscanned the network for anything. Nope. Nothing except muh lappy.
2) Plugged back into my network and tried DHCP. Scanned my network and saw an unknown device with ports 22, 80, and 443 open. That was it. Logged in via web interface with user admin password admin.
3) Set up the voltage, set up the pool information, and off I went.
After the fact, I discovered that, out-of-the-box, the SP20’s report back to Spondoolies via a handy website at myminer.io, that allows you to easily configure your machine.
Official setup instructions are available here:
https://cdn.shopify.com/s/files/1/0389/3233/files/SP20_Jackson_Quick_Start_Guide.pdf?4248Main screen turn on: Running the SP20 at 40% fans (The lowest available through the menus) runs at ~81dbA. WAY too loud for a bedroom to sleep in, so off it went into a spare bedroom that had an S3 and a Bitfury 500GHs rig still running.
![](https://ip.bitcointalk.org/?u=https%3A%2F%2Fi.imgur.com%2FOEKdMGd.jpg&t=665&c=4-nhlY7meLIt5A)
3 Bitmain S3's and an SP20 - Amazing to know the SP20 is more efficient than the 3 S3's combined !
![](https://ip.bitcointalk.org/?u=https%3A%2F%2Fi.imgur.com%2FzYgsaCB.jpg&t=665&c=dcU-oXS42V0KNA)
Changing of the Guard - Bye bye 500GHs Bitfury rig. Hello SP20 - Both the S3 and the SP20 are pulling ~1150W at the wall for ~1.7THs.
![](https://ip.bitcointalk.org/?u=https%3A%2F%2Fi.imgur.com%2FEalcXyE.jpg&t=665&c=o6IcgwYpUXiwIQ)
Some measurements
![](https://ip.bitcointalk.org/?u=https%3A%2F%2Fi.imgur.com%2FeIzTo5X.jpg&t=665&c=R28FRLkFXqCL4A)
Some more measurements
Conclusion: The SP20 is the most efficient and powerful piece of mining gear I have ever used, that comfortably runs on standard North American residential circuits.
Given the choice of purchasing 3 S3’s vs a single SP20, the choice is clear that the SP20 is the winner. In closing, it’s awfully tempting to pull the trigger and buying a bunch more SP20’s to replace less efficient A1’s and S2's.
Thanks again to the Spondoolies team for this awesome promotion, and allowing some of us to review their units. I'm very glad to see they have not forgotten about hobby/home miners, and I look forward to their next product offering geared towards us !
The SP20's are available for purchase here, currently priced at $659 USD.
http://www.spondoolies-tech.com/products/holiday-special-sp20-jackson-shipping-from-stockMaster list of reviews as part of this promotion follow.
1)
https://bitcointalk.org/index.php?topic=895085.0 spiccioli
2)
https://bitcointalk.org/index.php?topic=895798.0 Xian01
3)
https://bitcointalk.org/index.php?topic=896161.0 johnyj
4)
https://bitcointalk.org/index.php?topic=896065.0 Mushroomized
5)
https://bitcointalk.org/index.php?topic=896004.0 John (John K.)
6)
https://bitcointalk.org/index.php?topic=896134.0 SaltySpitoon
7)
https://bitcointalk.org/index.php?topic=896656.0 notlist3d
8.)
https://bitcointalk.org/index.php?topic=896910.0 THE JOINT
9)
https://bitcointalk.org/index.php?topic=897151.0 Dabs
10)
https://bitcointalk.org/index.php?topic=896913.0 Syke
11)
https://bitcointalk.org/index.php?topic=900307.0 goxed
12)
https://bitcointalk.org/index.php?topic=898952.0 blazedout419