Topic: Cairnsmore1 - Quad XC6SLX150 Board - page 106. (Read 286370 times)

Thanks for your insight into VHDL.
My initial look into VHDL vs Verilog was just a quick over view of example code and it looked quiet simple to pick up, maybe I too quickly judged VHDL.
If over the next few days I feel confident I understand what I'm doing I'll be asking to add a programming cable to my order, since It's my understand it is needed to reprogram these.
I have a background in both game engine development and commercial programming in C based languages. I've done it both as a hobby and for a job.
At least if I learn how to program these, I can have fun with them, rather than just make a bit of money.
You never know, if I get good at it, I can release them for the good of the community.

Any updates on the status of built-in USB programming and the packaging situation yet?

Regards

PS good to see you're looking at possible bitstream enhancements for future

It's an interesting business model and it will suit a lot of people. I don't have a problem with that approach. someone has done some work and they get rewarded for it. We do think these hashing rates can be achieved if not more in a Spartan-6. We will have a look at this although maybe not for next week or two while we are smoothing out the assembly line.

On languages both VHDL and Verilog have similarities and relationships to C. VHDL probably is now the closest although the more advanced System Verilog is in there too. VHDL tends to have a bigger base in Europe and in the FPGA community. Verilog is strong in the US and in ASIC teams. We work with both but strongly biased to VHDL which is 80-90% of what we do. Things like "types" and "overloading" are used in VHDL and a very familiar concept to a C programmer. C programmers tend to have most difficulty dealing with the parallelism. It's a bit different handling 10000 things happening on a clock edge to 1 thing happeing in most CPUs.

Yohan,

Any thoughts on using the newly released http://www.tricone-mining.com bitstream in the future?

(I understand that currently the most important priority is just getting the basics working first but thought I'd flag it up for you as something to look at)

It can apparently reach 315Mh/s - typical is around 270Mh/s (which is incredibly impressive). It uses a signcryption commission system, which equates to donating ~5% of the chips hashrate to tricone-mining, but the bitstream itself is free.

Regards

Thanks so he prefers VHDL. Interesting, guess I'll keep reading to find out why.

I've done part of this http://hackaday.com/2011/12/30/so-you-wanna-learn-fpgas/
Must make more time free to do more, but at the moment diablo 3 is so much fun

I think it is wise not to jump too quickly into ASIC. There is a lot on the horizon that could effect the market for it.
Also ASIC are notoriously expensive and a big investment, for both the end-user and manufacter, can't blame them for not wanting to jump into it without seeing the success of their first product. Which is quickly looking like one of the best FPGA boards on the market at the moment.

Btw Yohan, I'm tempted to jump into learning a HDL to create a bitsteam, or improve one, any recommendation on where to start?
Most of my programming experience is in C, C++, C#, PHP, etc. Is the Spartan-6 partial to a specific HDL?
I like the look of Verilog, seems a bit better imho than VHDL (Both popular choices apparently).
Also with it's appearance being "C-like" I think I'll pick it up quickly.

If an ASIC is the answer we will consider it. However I have my doubts about the economic viabilty of an ASIC approach. As has been discussed elsewhere I would consider if the Bitcoin market will remain stable. Hardware costs are actually part of Bitcoin stability and if you get an ASIC at low cost I suspect instability and maybe collapse might be the result.

A lot of this depends whether there really is a proper ASIC, what technology it uses, and what BFL sell it at. I won't add to the debate about how they fund that. They may of course be going for a last big bang, make big money quick, approach where Bitcoin ends up being the casuality.

I would also not rule out that we could put together a serious challenge using FPGAs. Cairnsmore1 is our initial product and we have played very safe with the technology so that we could deliver on schedule. That was an engineering and management decision. It also doesn't mean we have showed our best techology yet. That's not to in any way suggest Cairnsmore1 isn't a good product. I am very happy with what we have done now on at 6 weeks into the project and it will be a good for the customers that use it.

I think for the moment we wait to see what BFL actual releases. There is definate an element of trying to spoil the market with lots of bluster about what they are bringing. Enterpoint won't enter into silly games like that and we will concentrate on actual designing and producing good products. When we are ready we will talk about what is coming. For the moment our main concentration is getting Cairnsmore1 to customers as the best solution today and the team are working hard to achieve that.

Yohan

September 2011 announce ship March 2012 and still two months behind on the orders.

Its all part of the plan you people around here have proven your willingness to give them your money months in advance of delivery already, free product development financing every businesses dream not to mention the already locked in profit on them boxes as well doing it that way. Oh and these boys do ASIC design as well so they know what they are doing there too.

An ASIC is exponentially more difficult to to produce. BFL claims to have been working on their product for a while, and I've been going back and fourth with them in email, and they might have hinted that they will be accepting orders on the date of the unveiling, which would be awesome!

Time will tell if it is as good as the spec but the F12 has a 6 year warranty and I am sure I saw a operation lifetime spec of 100K or 150K hours lifetime which is believeable given the type of bearing it has. The one thing they could use to improve is their website.

Yohan

Because I think we have different definitions of silent. My HHE undervolted to 5 with the GPU fan shut off and all the other case fans shut off, its almost silent. The slowest AFB1212 undervolted to 5v should be dead silent and last for about 15 years. Those two consumer fans should last about 3 before they quit.

Yeah.. that is downtime that some of us can't stand.  More quieter fans, watercooling and remote locations are all valid options. Immediately wanting to cram a "loud" fan onto a FPGA board because it is industrial but only running the board when you aren't sleeping makes no sense 

I tell myself: on a spaceship/the ISS they have also life supporting whirring stuff Yeah, my own personal spaceship
but undervolting made it a little space capsule

BTW _subed and soon paid, deciding if I take a lonely "ion driven f12 space ship" or the whole fleet in one bombardement in 1-3 weeks....


choices.... (imagine the "ALIENS" meme)

I can hear my mining hardware standing in the yard.

Nope, I shut my computer off when I go to bed.

The argument to drive a e.g. 12V fan at a lower voltage to be not so noisy is true for nearly every fan. The big question is how much airflow does the fan still provide under this condition.
BTW: Driving an AFB1212s with only +5v is out of the specification.

If your GPU setup is so noisy it shows me that you don't have to care about the noise. That's fine for you, but not automatically true for everyone else.

The original suggestion (not my one) to use Silenx fans instead of Arctic F12 fans goes in the direction to use more quiet fans with better airflow.
All I've said is that the airflow of the Silenx fans is NOT better and the Silenx fans are only slightly quieter that the Arctic F12 and this is simply true.
I didn't compare only the datasheets. I compared the fans (from much more vendors than this three) by my measurements.  

There are also arguments to use other fans. But I think the Arctic F12, and the possibility to change it to another, is a good 'standard'-fan for the board.
I would not put the Delta fan in my BOM for THIS product.

The AFB series from Delta is loud compared to the airflow/noise ratio some other fans achieve. If you have other requirements, which let you live with this specific disadvantage, it's fine.

As a professional engineer in the industrial electronic business I've also an addiction to industrial components. But I don't see a reason why this specific application needs a super ruggedized high-end fan, which costs also a lot of money. I also don't like your fast, lump-sum statement regarding 'Chinese shit'. Delta is also producing in China, which is no problem for me. In my working life I had to design a power-electronic hybrid circuit for Delta electronics. My experience with them over years and the way how they produced it and handled Q-issues was everything else than good. This is the reason why this component will now be produced by a German company. But we are getting Off-Topic. I think I've said everything.

A molex connector is actually capable of drawing a lot of wattage, at a max of 187 Watts.
Not recommended to try do that of course.
Assuming that is you are taking from both the 12 and 5 volt, as they can carry upto 11amps each.
So your talking 132 Watts and 66 Watts respectively; going over 110W per strand you'll like encounter heat issues.

In comparison the 6 pin connector is rated at 8amps but will only handling 12volts; it however is rated at 75Watts.
I assume then, the molex connector is only being used for it's 12volt pin(s). Forgive me if this is actually stated.

So with this in mind, I would personally keep it to 1 per molex. If you have a lot of molex connectors on one strand you will have to limit it to two per strand. Just because I don't know for sure this FPGA won't go over 50 watts.
The Seasonic 1250 Gold has 8x 6+2 pins and 8x 4 pins connectors should you should be able to do that configuration without a problem.
Hope you got something good in mind to deal with the heat.

Keep in mind it's rarely the connector itself, it's more commonly the wiring leading to that connector that ends up being your limiting factor on most ATX PSUs. These boards should be drawing somewhere in the ballpark of 50W per board. So at 12VDC that's a little over 4A.

A lot of PSUs use 18AWG wire, some (nice ones) use 16AWG.

18AWG Wire when used for Chassis Wiring is only rated for an absolute max of 16A (and at that, with cheaper wire sheathing will likely get bloody hot)
16AWG is rated for 22A in the same condition.

So based on that, if you have 4x molex connectors on a single strand fed by 18AWG wire, the most you could cram safely on that wire is 3 boards. But I wouldn't recommend going over 2 boards. The PCI-e power connectors have more wire pairs (And some higher end PSUs use 16AWG for those higher current connectors) so in that case you can likely split a few more off of it. Just make sure to load it evenly, and mind safe wiring practice and you can likely use up that 1000W fairly effectively.

Personally I find that the limit I like to load on a single strand of 18AWG wire is about 80-100W before it gets "warm" to the touch, but not hot. Beyond that and you're getting into "asking for a fire" territory.