I read some posts where some of you were having good luck with Pi 4's.
Where are you guys getting the Pi 4 from? Newegg doesn't have them and that is where I usually buy my tech from since they accept Bitcoin.
Haven't had a chance yet to test with a Pi 4. Most seem to be out of stock as they are selling fast lol. I do have a Odroid xu4 on order and 'should' be here by July 19th. Looking forward to testing it. As for the Pi 4 https://www.adafruit.com/product/4295?src=raspberrypi is one site I usually check for SBC's and other items to tinker with. And here is a listing of other locations that possibly may have some: https://www.raspberrypi.org/products/raspberry-pi-4-model-b/
I really hope they fixed some of the issues experienced with the Raspberry Pi 3 b+. Bandwidth is the issue with the Pi from what I have experienced both using it as a controller for the r606 in mining and now as a NAS. The Gigabyte Fast Ethernet is rated at 300MB/s however I am not getting anywhere near that. I tested after setting this up by uploading a 1.7GB zip file to the Pi NAS. Since the Pi defaults to Gigabytes Fast Ethernet speeds would range from 40Mb/s when it started up and then drop down to an average of 1 - 2 MB/s transfer speed. With many ups and downs in the transfer with a few times hitting 0 for a few seconds and then firing back up again. I believe these stutters are possibly the issue some of us miners had with the Pi.
I made a change that made the transfers a bit more stable (didn't drop down to 0 as the default setup does) however is a bit slower. If someone wants to test the following changes in mining I'd appreciate it. As it's a bit much effort for me to clear out and rebuild this all over again
First:
sudo apt install ethtool
Once you have this installed you will need to determine what your ethernet device name is. It 'should' be
eth0. However not always the case. Since I reformatted my Pi with Open Media Vault and they are using Armbian 5.46 (GNU/Linux Stretch) instead of raspberian, my device name was different. To determine what your device is do the following:
dmesg | grep eth
For me I received the following:
root@raspberrypi:~# dmesg | grep eth
[ 3.321603] lan78xx 1-1.1.1:1.0 enxb827eb604bd5: renamed from eth0
root@raspberrypi:~#
And this shows that my device was renamed from
eth0 to
enxb827eb604bd5. Hopefully if you are using raspberian or NOOBS it'll remain eth0.
Now do the following:
sudo ethtool -s DEVICENAME speed 100 duplex full
This reduces it from 1000 to 100. I noticed better performance going backwards
Transfer speeds this route averaged at 11 mb/s so it's not great. However no stutters and it never dropped to 0 as it did at it's defaulted state. You can always change it back to 1000 or just simply reboot for it to use the standard defaulted speeds. I'm just curious if this would normalize some of the r606 mining.
** edit**
I may end up redoing this anyway and testing. Figured while I have the time I'll go ahead and make a video 'how to' on the newpac installs for Raspberry. Can give this a test as well while doing so.
** Edit ** 7/13/19
Ok reformatted my micro SD and instead of using Raspberry NOOBS for the OS I loaded Raspbian. Reinstalled all of the latest gekko software and fired up both the newpacs and the r606's. Before making any tweaks I ran the miners as is. The newpacs, no issues, even at 450mhz. Although one wanted to keep restarting. It didn't do this on my linux desktop however. So not sure what to think on it as of yet. The r606's same as my earlier posts in this thread. One thing I did notice, I use prohashing as the pool, it would take forever to get a share. And speeds would reach up to 550 (I had it set to 700 and volt 6) and back down to mid 400s on the r606 machines.
Next I stopped the miners and changed the eth to 100 duplex full. Mixed results with this. The pros. Started picking up shares on both the newpacs and r606 almost immediately. Made it up to 600Mhz @ 805Gh/s average and they appear to be stable. The cons.... Had them both clocked at 700MHz on volt 6. One dropped to 584Mhz (better than original test dropping to mid 400s). And 2nd r606 stayed at 600MHz. On the Pi even with this tweak they wouldn't hit their mark.
So at this point I believe there are still some limitations with both the processing power of the Pi and it's bandwidth. Dropping to 10/100 instead of 10/1000 did see improvements however.
And my recommendations remain, if you only have newpacs, the Raspberry P 3 B+ or earlier models would be ok. If you are planning on running R606's or both, then I highly recommend a devoted desktop with a modern CPU and RAM to handle them. Or possibly a stronger SBC. There is the new Raspberry Pi 4 that has just been released that a few others are testing out soon. I will have a Ordroid XU4 by end of next week with it's 8 core cpu (although still ARM based) and 2GB of RAM. Will update with results as they come available for those looking to have smaller controllers.
And those like me that will have a Raspberry Pi just sitting around, they make a decent controller for a home NAS setup (instead of using 'the cloud'). Using USB sticks for the storage in a raid setup for those of us that have plenty of those just collecting dust. Or usb HDD (external power source however) and have a 'home cloud' setup
Thanks
I need to buy it ! 
