HashFast is one of the few companies that was promising 28nm hardware in 2013. As some of you might now, they are in bankruptcy under chapter 11 and have an external CRO (Chief Restructuring Officer) appointed, meaning that the management is not the same as the one that bankrupted the company in the first time.
I was contacted a few days ago by Simon Barber, telling me that they were finally able to secure a very good pricing for manufacturing on their old but proven rev3 “EVO” board design. It’s a single board single chip liquid-cooled miner that typically can be pushed up to 750GH/s.
Hashfast is offering a kit consisting of:- A tested good rev3 ‘EVO’ board
- A CoolIT ECO-III liquid cooling system, with Sanyo Denki high speed fan.
- A bolster plate, thermal pad and indium foil square
Pricing:The price per kit will be
$260. Shipping, handling, any taxes or import duties and power supply are not included in the price. To complete the system a PC running cgminer and USB cables will also be needed, as well as common hardware like screws and hex standoffs. The kit will have to be assembled by the customer.
Minimum order quantity:The above pricing can only be reached if HashFast places an order for 2000 boards with their manufacturer. The goal of this thread is to collect interest on this product, in order for HashFast to be able to place an order.
Boards will ship in boxes of 20 from China (FOB Shenzhen). Coolers, fans, bolster plates, cooling pads and indium foil ship from the USA. The customer will be responsible for purchasing screws, standoffs and PSU needed for final assembly of the mining rigs, and doing the final assembly of the board, cooler, fan and PSU.
Orders must be placed in multiples of 20 kits.
Board performance:With the provided liquid cooling system, board performance will vary depending on how carefully you place and tighten it to the board, and what mounting hardware is used. Please refer to the attached emails for a full explanation on how to obtain up to 750GH out of those boards.
Logistics:Once the group buy is arranged the ASICs take about a week to be tested and shipped to the chinese board assembly shop. The chinese supplier HashFast is using promised to assemble and ship the first 1,500 boards within 18 days from the reception of the order and parts. That means that this thread needs to collect enough preorders to make the batch worth it’s run, wait for the chip testing and shipping, the board supplier 18 days and then for the delivery courier. Hashfast is waiting for confirmation on the lead times for the bolster plates, cooling pads and indium foil. It is expected to be less than the lead time for the boards. The kit can be operated without the bolster plate/cooling pad/foil at a reduced performance.
Original emails:Initial email:Hi Davide,
One of our China manufacturers has just offered us very good pricing on their remaining stock of rev3 boards. This could potentially enable a rev3 group buy. We can supply them with the long lead time parts, and the ASIC, they can produce the board, and we can supply a cooler. [...] Boards ship from China, coolers from US or Canada. The first 1500 boards can be ready 18 days after order placed according to the manufacturer. The China manufacturer has asked for a minimum order of 2000.
SimonDetails about board performances:Yes, seems OK. I think it is also very possible that the manufacturer will accept a slightly smaller order, if offered. We need to coordinate how the logistics will work. [...].
In general getting something out there sooner rather than later would be good to gauge interest while we work out the logistical details.
With a bolster plate and indium foil (not included in what I've talked about so far) the boards can do 700GH and with careful setup 750GH can be achieved. Note - these numbers are based on our previous chip testing regime - the higher volume chip testing we are doing now could allow a small number of lower performing chips to be passed.More about board performances:I've double checked with one of the engineers about speeds, before publishing anything. [...] For the basic board / cooler combination with good thermal grease without bolster plate, he thinks that it's easy to get 600MHz, and with a little skill 700MHz. Higher speeds are possible, but you need to be very careful in how gently and evenly you tighten the cooler. This corresponds to theoretical speeds of 461GH/s or 538GH/s. I'm going to double check these numbers with our China manufacturer, who has done their own extensive testing too. To get higher speeds requires a bolster plate, so the board does not distort and warp when you tighten the cooler down. For highest speeds you need indium foil instead of grease between the chip and the cooler. I'm double checking the numbers for the boards with bolster plate and foil, but historically 700GH has been easy and 750GH with careful setup. Bolster plates are not expensive to get made, but would complicate the project. (You need the bolster plate, a piece of thermal pad to go over it, and a piece of indium foil between the chip and the cooler).Efficiency at lower hashrate:In order to set up the boards without the bolster plate, and still achieve good thermal mounting, our China assembly partner uses jig with a clamp that evenly holds the cooler down onto the board, and applies a good pressure, and then the assembly worker screws the cooler on, just turning the screws hand tight. This jig allows the unskilled assembly worker to achieve good, consistent, even mounting pressure.
The same can be achieved by hand, as long as you are careful to do the tightening evenly. One of the software setup tools loads up the chip with dummy work, displays a continuous readout of die temperature so you can watch for even thermal contact as you tighten up the screws.
BTW The china manufacturer reports that running the boards at 450GH he measures 0.8J/GH at the wall.Components required to push the board to 750GH:The bolster plate is custom for the board. I don't know of anything off the shelf that would work. They are not expensive, but I will need to get a quote to ensure lead time and price. We have already had a fair number made, so this would be a simple repeat order. A piece of thermal pad is needed between the bolster plate and the board to prevent the metal plate from shorting the components on the bottom of the board. These come in 20x40cm sheets from a chinese manufacturer, and need to be cut into squares with scissors. Thirdly the indium foil comes from the Indium corporation, I will need to check if we have any stock left, or lead time to order.About logistics:The biggest question is logistics - if all of this goes to a single buyer, who can do the final assembly, then it's relatively easy. If many small buyers are involved then it's more work.
No problem - I can arrange the ordering of bolster plates/pads/foil.
Our China manufacturing partner will ship the boards to multiple customers though. They need a shipping solution, and I have offered to send them the design for the shipping solution we used to ship boards to Ciara in Montreal. This solution is a specially designed cardboard box that takes 30 boards, and offered good protection for them.
The China partner is using the same coolers as us, but got better performance numbers than our engineer reported for the stock support/grease configuration (which we did not experiment with much - we focussed on the enhanced bolster plate/foil). They got 550GH from 98% of their boards, and 600GH from about 70% of the boards. This is at 35C ambient, so would do better in a cooler place. Given this variability I think we need to offer the boards at a fixed price per board, and let people know the different performance range that can be expected, so they can calculate $/GH themselves. In addition they stated that, like us, the exact process of mounting of the cooler to the board is critical. Applying the pressure evenly and gently is important. Doing it well makes a big difference in performance, and since we'd be leaving this to the end users we can't guarantee what their work will be like, so we can't make any statement about performance.Shipping details:Getting the shipping boxes made for the boards will not cost much, but shipping will have to be insured, to make sure any damage loss is covered. These prices won't allow much buffer for handling returns.
We would ship coolers from the USA or Canada in boxes of 4, and fans in boxes of 20. The end user would need to purchase a PSU, screws, and standoffs to complete their rig.
Also - given that the coolers come in boxes of 4, the fans in boxes of 20, and the shipping boxes for boards would typically carry 30 or so (but can be made any size), I think it might be difficult to support customers ordering 1 or 2 - since it will require a lot of repacking. The whole point of a group buy is to reduce the number of orders (ideally to 1) so that the consolidated shipping/handling makes all these things easier/cheaper. Perhaps an ordering unit of 20 boards would work - although more would be better. The China manufacturer can have the board shipping boxes made up to carry 20 boards, and we can ship 5 boxes of 4 coolers and 1 box of fans to each customer. We will also need some packaging (a box) to ship the 20 coolers, 20 fans, 20 bolster plates, thermal pad material for 20 boards, and 20 pieces of foil. 
