
Hey guys, a few months ago we talked to you about using a FPGA to do cryptomining and showed a comparison of CPU, GPU, FPGA and ASICs to see how the profitability increased by increasing the hash to watt ratio. Looks like we hit a chord as it became one of the most popular articles on FPGA mining on the internet! Thanks guys!
In the article I mentioned that we would post updates as we loaded/built the bitstreams. This has been an adventure and a big challenge! We had some initial success by loading different bitstreams, but found that they were old algorithms that didn’t provide much profit in todays difficult (pun intended) mining environment. During our development work to build new algos on our FPGAs, Richard from TUL contacted me and wanted to see if I could get something working on the TUL KU115, similar to the KCU1500. This is a pretty amazing board and we took the challenge head on!
Specification of the Xilinx KU-115 UltraScale board

First off the KU115 has a Xilinx Kintex XCKU11502FLVB2104E FPGA with 1.4k LE elements and it has 16 GB of DDR4 (3 at 72bit and 1 at 64bit) with a clock speed of 300Mhz that can be overclocked to 500Mhz. It has a significant heatsink on it, but I do wish it had a fan as it can heat up quite quick. It supports PCI Gen3 x16 allowing a 32GB/s transfer speed. Nice!
All in all this board is pretty fantastic for its price!
It took months to get up to speed, but I am happy to announce that we have a keccak and keccakc algorithm to release! This is designed for the TUL KU115, so this bitstream will only work on this board for now. If you have a different board, we can potentially work at a partial reconfiguration.
Hardware Setup
Our setup is an older machine that I had sitting around, so honestly this is not ideal and likely IS SLOWING down the possible hashrate. The computer consists of the following components:
Test System | |
Hardware: | AMD Athalon II X2 250 2.5Ghz MSI MS-7641 (760GM-P23 (FX) motherboard 8 GB Corsair DDR3 1333 1TB HP Blue 7200 RPM JJT (logo looks like WT) 450W power supply Ubuntu 16.04 (with all updates) |
Case: | ATX Case with 4x bays |
Mining Results
So how did this stack up? That is why we are here right? For using an old computer to test it, it did pretty good for our first bitstream as the keccak algo doesn’t use much of the memory on the board, so it is just hashing off of the chipset. After testing for a few weeks it looks like it is most stable at 2.5Gh/s mining keccakc @ 100W and actually is a bit lower under standard keccak. The issue I ran into was that since it doesn’t have active cooling on it, the clock and cores could not be increased even though there is the potential there by a little bit. I ended up using a box fan blowing into my case to keep it at a nice 70c all the time. Without the box fan (which happened after my kids accidentally unplugged it) caused a rapid shutdown of the computer, good thing we implemented a shutdown sequence on overheat. This feature is limited so make sure you monitor your heat and gently increase the number of cores. The proof is in the pudding as they say though, here is a pictures & video demoing the unit below.
I worked with a friend to build this bitstream and I want to make sure to honor his work on this, so there is a 5% dev fee on using it, which is built into the bitstream. We have a custom build of ccminer to help optimize the FPGA and allow for easy configuration. This runs on Linux currently, but we are working on building one for windows.
We have the keccak miner and bitstream ready. Click here to download it!
Here are some instructions on how to install and configure the board for the first time and for use:
Please download the file and give your feedback and issues you may have.
Conclusion
We are super excited to officially release our bitstream and looking forward to your comments about it! We continuing to build more individualized bitstreams, but working toward a DIY approach to make building bitstreams easier. It is a huge task but we are working toward this goal! Thank you all for your patience, support, kind words and support. I hope you find this as exciting as we do!
If your interested in purchasing the TUL KU-115 we have a contact at TUL who is giving discounted pricing for our readers at $2000, here is his contact info! Thanks Richard!
Richard Lo
Tul Inc.
Email: richard_lo@tul.com.tw
As always I hope this is one step closer to you living to learn free each and everyday!

For the past 20 years I have been advocating and teaching about Renewable Energy and Alternative fuels. I worked in IT for 9 years and ran a few IT businesses during that time. I have worked wind turbines and in fuel cell technology and I currently teach college courses full time in Renewable’s and Alternative fuels. I am passionate about technology, building things, family and having fun outdoors. I love sharing and helping to make the world a better place in my own way.