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...and the prime suspect is Avalon. Stress out the customer support of the competition a little bit...
I registered for news from Avalon just a few days ago, in order to be in the loop about batch 2 and subsequent batches, but not in my wildest dreams would I have thought that they harvest my password and use it to place 5 fake orders with BFL for a total of 8 FPGA singles.
If the Avalon folks are innocent of this bizarre scheme, I apologize.
But if it walks like a duck, squawks like a duck...
-Harry C.
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So my Mini-Rig was scheduled for delivery on Tuesday, but when I arrived at my mining office at 10:40, it turned out that I had missed the FedEx guy by less than half an hour. Another 100 bucks down the drain. Having once owned an airplane, I've acquired a very high tolerance for wasted Benjamins, however, and merely made sure that I won't miss him on Wednesday, by explaining the situation to my manager and taking the company-issued notebook with me when I left that evening. For the first time ever, I would work in my sauna-like mining office - only until the delivery, of course.
After giving the FedEx guy a Coke as a tip and savagely ripping open the cube-shaped package, I found the Mini-Rig upside down, its tiny rubber feet in the air. After wrestling the beast into an upright position, and noticing (but ignoring) something rattle inside, I plugged both of its USB cables into a prepared Netbook running cgminer 2.6.4 on Ubuntu 12.04. I plugged in the power cable, and - bingo - all 17 miners came up. Time to go to my daytime job.
This could have been a Hollywood-style happy ending, but, as it turned out, my joy was premature.
Upon arriving at the daytime job, I immediately saw that the hash rate of the Mini-Rig was not the advertised 22 GH/s, but just 16 GH/s or so.
Facing a deadline on Friday, a last-minute feature request which involved generating an .rpm on Ubuntu (!) and integrating this into my employer's build system, which is NOT based on "make", but on something quite esoteric, I could not spare the 20 minute round trip time and drive to the mining office. Diagnosis and repair would have to wait till the evening.
Back at the mining office, which is 10 minutes from my daytime job, I immediately saw what's going on: 6 of the 17 boards inside the mini-Rig were offline. Restarting the rig resolved the situation only for a very short time. Soon, it was back to 6 failed boards.
Shipping the rig back to BFL would be the coward's way out, and would cost me several hundred dollars in lost mining revenue. So I decided to open the case and have a look.
The U-shaped top/front/back is secured to the more massive, also U-shaped bottom/left/right by an impressive number of hex screws, probably around 30 in total. The last six are easy to overlook as they sit at the bottom of the case.
Lifting the top/front/back part up and turning it upside down before placing it on top of the main chassis in a perpendicular fashion revealed the guts of the mini-Rig. There are 3 populated "floors" housing 6 circuit boards each, one floor - hard to see which one - obviously missing a board, for a total of 17 boards.
The top floor is not populated, and thus someone with 4 mini-Rigs could turn them into 3 fatso-Rigs and host them at Inaba's data center for $900, saving $300 per month.
The LCD in front only displays static text - I assume that grand dreams of a CGminer feedback path to this display had been sacrificed on the harsh altar of software engineering reality months ago.
I also identified the source of the rattling: One of the 17 circuit boards had worked loose during shipping and was merely resting on its standoff, instead of being secured to it. Quite easily the board could have come to rest skewed or even diagonally, with one of the standoffs short-circuiting and frying the board. I was incredibly lucky that all 17 boards still worked - but 6 of the 17 would always drop off after a little while. Or would not come up in the first place.
I went to one of my other, BFL Single-occupied, mining offices, where one netbook was handling 9 Singles, but another netbook only one Single (don't ask). For the sake of science, I unplugged the lonesome Single and carried the netbook to my mini-Rig office. There, I plugged each of the two USB-cables of the mini-Rig into a different Netbook, power-cycled the mini-Rig and observed the outcome. Would this resolve the problem? Not fully trusting Netbook hardware nor CGminer stability, I think a $100-a-day device like the mini-Rig deserves to be plugged into two netbooks, anyway.
It did *not* resolve the problem. But it shed some more light on it.
One netbook had 8 boards mining like a charm.
The other netbook only saw three working boards - six boards going dead instantly or after a little while.
So, at least I had bisected the problem and immediately proceeded to bisect it again. Why are 3 boards working, but six are not?
I looked at the USB hub. The mini-Rig sports two 10-port USB hubs - I know them very well, as I have about ten of them myself. In fact, I use them to hook up my Singles to various netbooks and notebooks. None of the USB hubs in the mini-Rig is externally powered - something which would be quite easy to do, as a PC power supply, which is used in the mini-Rig, does sport 5V wires.
As the old saying goes, for want of a few butt connectors (they are really called butt connectors, I'm not making this up), a mini-Rig was lost. Or 35℅ of it, at least. But I'm jumping ahead.
Each of the 10 ports has an activity LED, or maybe it is a power LED. I immediately saw that while 3 of these LEDs, the ones closest to the USB uplink, were steadily on, the other 6 were frantically blinking in blue. Blue as in "Code Blue". I walked to one of my other mining offices where I keep the stash of 10-port USB hubs, grabbed one of them, and walked back to the mini-Rig office. Who says that Bitcoin mining doesn't provide exercise...
I then plugged the new 10-port hub into another USB port of the netbook with the 3 working and the 6 sick miners, pulled out one of the Mini-Rig cables of the code-blueing BFL hub, plugged it into my own hub and hit 'q' on the CGminer console.
I run CGminer from a trivial shell script with an endless loop, so 'q' really means "restart" here and - bingo - I had 4 working boards and 5 non-working ones on this netbook. BFL hot-glues the USB plugs onto the hubs, but it's cheap glue and cannot stop a determined Bitcoin miner. Soon I had 5 working boards and 4 non-working ones, I worked loose the third cable, plugged it into the new hub, hit 'q' on CGminer and - I had 9 working boards, in addition to the 8 working boards on the other netbook. Unplugging 3 cables had resolved the overload condition and the sick hub had recovered, now successfully handling 6 USB cables.
Since then, the mini-Rig is running at approximately 24 GH/s, and I'm a happy camper.
However, I still have a few recommendations for BFL.
1. When fastening a board to standoffs, or, in fact, anything to anything at all, please use a thread-locking adhesive. It will prevent a screw from working itself loose during shipping. I have received Singles with loose screws rattling around inside, and now the mini-Rig with a whole board rattling around inside. Stop the rattling, and I promise I'll stop the tattling.
2. When a cheap hub from China boasts it's a 10-port hub, that doesn't make it so. Take this spec with a grain of salt, and ship a mini-Rig with three hubs, loading each one with 6 plugs only. Even netbooks have three USB jacks. Three cables coming out in the back is still OK.
Or, alternatively, power the hubs. 5V cables are available a few inches away. Use them. Two words: "Butt connector". Two more words: "Crimping tool"
3. There are horizontal aluminum plates or steel plates, intended as fan baffles, inside the mini-Rig and they just rattle around inside. They are not bolted down. This is very sloppy, as these plates could damage something during shipping, for instance one of the boards in case a board comes loose (as it did). As I said, my mini-Rig arrived upside down.
Regards,
Harry C.
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I just got this via email, I'm not affiliated with them:
LargeCoin is pleased to announce that we are now taking deposits against pre-orders of our first dedicated, ASIC-based mining appliance, the LC 200C Integrated Mining Unit (IMU). Deposits will be held in third party escrow until final product delivery, which is expected in July 2012, and will be refunded if the product cannot be delivered on time. And yes, you can pay with Bitcoins if you prefer. Additional product details, along with terms and conditions, are found toward the end of this message.
If you would like to be contacted about making a pre-order, please use the following Google form to let us know:
[url removed]
PRICING AND DEPOSIT DETAILS
The C200 IMU is priced at USD $30,000. We are selling 25 units initially, with more to come later in 2012. To secure your place in the line, you must make a $4,500 deposit, which will be held in escrow by a third party until product delivery. You and LargeCoin will sign an escrow agreement to this effect before any money is transferred. The deposit will be returned to you if product delivery does not take place by July 31, 2012.
==============================================
PRODUCT DESCRIPTION
The LargeCoin C200 is the world's first purpose-built Bitcoin mining appliance. Designed to fit within a standard 1U of rack space, the C200 connects to the network using Ethernet, and starts mining as soon as it's plugged in to the wall. Mining is controlled via an online control panel hosted by LargeCoin, which allows you to direct mining shares to the pool of your choice and manage your entire LargeCoin cluster in one convenient place. Each C200 mines at 20GHash/s, consuming a mere 100W. Designed for high density operation, the C200 provides efficient movement of air and is suitable for operating in a fully loaded 42U rack (up to 40 units per rack).
Despite the incredible power efficiency and spatial density of the C200, it's priced competitively with GPU mining. When compared with GPU mining, the C200 consumes 100 times less electricity and 14 times less rack space, meaning there's virtually no operating cost associated with this device.
TERMS AND CONDITIONS
Your deposit guarantees that LargeCoin will ship you a C200 IMU by July 31, 2012, that the specifications of the final product will not deviate materially from the specifications shown here, and that the device will function properly when it is plugged in. When you receive the unit and connect it to the network, you will be granted a temporary mining license enabling the system to mine for a period of 30 days. When we receive the balance of your payment, a permanent mining license will be issued to you. C200 IMUs may be transferred and re-sold -- just let us know before you make the sale so that we can transfer ownership of your license key.
SHIPPING
LargeCoin ships to North American destinations for free. Shipping costs for other destinations will be born by the customer and must be paid in advance. We will notify you when the shipping date approaches and provide a shipping quote for your review and final approval. International customers should be aware that air freight and insurance may cost $2,500 or more.
90-DAY LIMITED WARRANTY
LargeCoin warrants that the C200 will function materially consistent with the specifications for a period of 90 days following device activation, which occurs when you plug the unit in to a network with Internet connectivity for the first time. If the device fails, you may return it to us at LargeCoin's expense for a full refund, or replacement unit. Devices that are dead on arrival will be replaced or refunded.
NO GUARANTEE OF MINING REWARD OR FINANCIAL PERFORMANCE
Due to the random nature of Bitcoin mining, and the large uncertainties in the Bitcoin economy and network, LargeCoin cannot guarantee that the C200 will solve Bitcoin blocks at a particular rate, or that it will generate a financial benefit of any kind. Mining profitability depends on a number of factors, including the selection of a mining pool, which may or may not charge fees that reduce the mining reward; changes in the Bitcoin mining reward calculation including but not limited to scheduled reductions in the mining reward; and fluctuations in difficulty factor. LargeCoin's warranties and guarantees extend only so far as the hashing rate provided by the appliance, and its level of average power consumption.
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Hi, I was aware that as a newbie I cannot post a forum post except to the newbie forum, but was never told that I cannot message another member.
Q1: Why is this crippling restriction omitted from the disclaimer?
Q2: Now many forum posts does it take to be able to message another member?
IMHO, people will just make useless posts in the Newbie forum to get around this restriction, thus it's pointless and a time waster for everyone.
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