Topic: X6500 Custom FPGA Miner - page 21. (Read 219951 times)

We are working on the next revision of the firmware, dubbed Overclocker firmware, which will allow overclocking (or downclocking) the FPGA. This should provide a boost over the rated frequency if the board is kept sufficiently cool.

Are their faster bitstreams in the works or is the 200mh/s going to be the top for awhile?

If anyone wants some of the #4 size standoffs that work on the  rev 2 boards, I have a few extra. just pm me.

He is not teasing.  I just picked up 3 that will ship wednesday.

They listed 10 in stock just a few hours ago and they're already gone!! We'll need to get through testing and packing some more boards before he lists more. Sorry about that!

Well I can *see* the heatsinkless board on cablesaurus again now. It even says "In Stock"... but when I go to buy it, it says:
"Products marked with *** are not available in the desired quantity or not in stock!"
(desired quantity 1 or 10 - doesn't seem to make a difference)

Stop teasing, Cablesaurus!

In the last run I did with that board before I took off the heatsinks, I ran 200 MHz for 26 hours without a single invalid on either FPGA. Unfortunately, we won't be shipping units with those heatsinks. The main problem is that we can find them in any reasonable quantity. Second is that they really are a little bit too big. The two mounting holes at the top edge of the board (the power side) are just barely blocked by those huge fins, so to stack with those heatsinks would probably require filing off a little bit of the fins to make room for a standoff. Not a difficult task, but it just means it isn't really the right fit for us to be including those as the stock option. It's looking like we will most likely be going with the Logisys Deepcool style heatsinks.

That said, if you want to use those Zalman ones or some other type, we'll also offering X6500s without heatsinks, at a discount. The first ones shipping out (early next week) will be without heatsinks and, depending on demand, plan to continue offering some without heatsinks.

Everything about your plan sounds great to me! I don't think you will need the powered USB hub. In my testing, I tend to make sure I have my hubs powered, but I have used them unpowered occasionally and everything seems fine. Here's what's drawing power from the USB cable:

FT232R (15 mA typ.)
3 x LEDs (3 x 8.5 mA)
2 x temp sensors (2 x 0.28 mA)

So, less than 50 mA. The 4 boards should be fine off of a bus-powered hub.

You're power adapter and idea to split to 4 of them seems perfect to me, too.

Good luck with your build and please share your progress with us!

I am planning an enclosure for 6500’s (up to 4). I want this to be very self-contained with only ports on the back for 1 USB and 1 Power and then have it distributed to cards. Is it recommended to have a powered USB hub?.  The plan is to have USB distributed with a 4 port hub internally but if it needs to be powered it will complicate things for me but should be doable.

For the power I wanted to get an adapter that splits 1 into 4 such as http://www.aartech.ca/cb-cctv-p4-power-splitter-1-input-4-output-barrel-connectors.html?utm_source=googlebase&utm_medium=googlebase&utm_campaign=export_feed

For the power I was looking at something like this ( 102w (12v/8.5A) AC-DC Power Adapter) http://www.mini-box.com/110w-12v-8-5A-AC-DC-Power-Adapter   with an adapter to change the barrel size.  I am not seeing very much that will provide the power I am looking for. I have used these adapters and power supplies from Mini-Box for other projects and I was thinking of just going with an internal power supply but it seems unnecessary and I am not sure how the power would be divvied up from it.

Still looking but I was hoping somebody may have input on the power/usb.

Does anyone have any experience on ordering these to the UK? price, customs, delivery etc

Are you getting invalids with these heatsinks?

+1 especially for the zalman

Any word on when we can expect to see them on cablesaurus, and what cooler they'll offer as stock (the zalman one?)?

Nice V3 is out!! I'll take some pics on monday when I get back to work! Also I'm testing out Fizzisist's fork of the MPBM and man oh man does it look nice so far! Kudos to the X6500 team on a good job thus far!

Those coolers somehow looks epic on that board! *thumbs up*

Nice results

I finally have some hard numbers on power consumption, and it confirms great O_Shovah's results shown here.

I did these tests on an X6500 rev3, equipped with Zalman ZM-NBF47 heatsinks. Airflow was provided with an 80 mm fan at the side, just like with the standard rev2 setup, except with a humongous-ized version of those little blue ones.



I measured the current and voltage right at the board, so this excludes inefficiencies of your PSU. I also checked many of these measurements at varying times during the day, so big changes in ambient temperature and never saw a measurable difference. I suppose there would be a difference if your heatsinks weren't doing their job, though. I plan to repeat the entire set of measurements on a different board with both the same heatsinks and a different set of heatsinks to see how much variation there is between FPGAs and between heatsinks.

It's interesting to see how much of an effect the different bitstreams have, despite clock rate. Clearly, the ztexmerge bitstreams are not just faster, but more efficient.



At 400 MH/s (which most people are using apparently), the power consumption is just 16.4 W.



Interestingly, all of the ztexmerge bitstreams have a linear relation between power and clock speed, so they all have basically the same efficiency. The 200 MHz build gets 24.4 MH/J.

Shipping is actually calculated automatically at the time of checkout, or prior to checkout while in your cart.

All FPGAs are shipped Express via USPS from Virginia, USA (Zip Code 22827.) Depending on the package size if ordering other supplies as well, this could vary greatly so it's hard to be more specific. You can calculate automatically from the site though to double check!

I'll be posting a new link on the site, to avoid confusion with any old links, once we're ready to roll.

I don't think it's quite that strong to actually case heat increase due to pressure/air friction. I think it's better for channeling air across the heatsink instead of blowing it about. However having said that I think you still need some airflow across the rest of the PCB - especially the underside of it. Ideally I'd like to have a giant heatsink on the underside of the PCB as well  and with a bit of airflow across both the top and the underside of the PCB (as well as the fpga heatsink of course) I think this board can run at 200 MHz with 0% errors and even in a mildly hot climate.

designed to increase pressure. Anytime air pressure increases heat happens.
Tho not sure if it's enough to matter in this level of pressure, most likely not, and the temp increase is in in the 0.0x range if even that.

I'm not sure if that would help -- I think it might just impede the flow of air (narrowing the aperture would increase back-pressure).