I have been intrigued as to how far the S3 can be pushed and have been doing some tests over the last few days, running each chip_freq setting for approximately a day to get a more representative average result for that specific frequency.
I did this with a batch 6 S3 powered by a Dell PS-2521-1D server PSU rated at 550 watts connected via 2 PCIe connectors.
I carried out the testing over 5 days on 5 different sppeds starting with the stock speed of 218.75, and here's a summary of the settings and results.
chip_freq | | freq_value | | timeout | | GH/s(avg) | | HW Errors |
218.75 | 1106 | 18 | 440 | 147 |
225 | 0882 | 18 | 452 | 117 |
250 | 0982 | 16 | 503 | 138 |
256.25 | 1406 | 15 | 516 | 155 |
262.5 | 0a02 | 15 | 529 | 200 |
I am not sure of the formula used to calculate the error percentage for the S3, however from the image below, you can work it out since I have all the values in there.
I was amazed how well the temperatures were kept down by the S3 compared to the S1. Of note though, is that I keep my rigs outside the house, covered to protect them from the elements but very well ventilated.
A note about the PSU: The Dell PS-2521-1D has three 12V rails each pumping out approximately 15A on a 200-240V line. Even more interesting is that the PSU cost a mere GBP 10.00 from ebay!
I am not sure whether I can push the PSU any further as I do not have an anmeter hooked up to show the power being gobbled by the S3 at the higher clock speeds, however, from my initial tests, it seems the S3 can be pushed further without much ado. Anyone managed to clock higher?
UPDATE: - upgrade to cgminer 4.6 - 13th Sep 2014I updated the overclocked S3 to the latest cgminer version 4.6 and below is the screen-shot after running for a day.
Note:
1. I am not sure what to attribute the drop in hashrate to, but its dropped from an average of 529 to 514 (approx 15 GH/s over a day).
2. Hardware errors have also gone up by 50%+, though the percentage is still low generally. I would not have minded this number going up if the hash-rate was maintained or bettered.
3. The unit's GUI is very clearly more responsive (though you can not see that here), but the value of discarded shares has shot up again (did I mention I reduced the queue to 10 from the stock 4096?). I know that number is not useful, but the slight increase in temperature and the fan speed indicate to me the unit is working harder than before. Infact, I can attest to it as I hear the fans ramping up (they have a distict sound over the other fans I use on other units).
All in all, I am seriously wondering whether this upgrade is worth it on a performance level. It is well documented that 4.6 plugs some security flaws that are open in the stock version, but I am wondering whether it is worth the "pain" of losing 15 GH/s over a day's hashing.
-------- DEPRECATED! ---------- version 4.6 is no longer available Oct 2014, use 4.6.1 below To upgrade to cgminer 4.6 follow this process.
1. SSH into the S3 and login
2. Issue the following commands sequentially.
a) cd /usr/bin
b) mv cgminer cgminer.bak
c) wget
http://ck.kolivas.org/apps/cgminer/antminer/s3/4.6.0-140908/cgminer d) chmod +x cgminer
e) reboot
To revert back to the stock cgminer (assuming you followed the above process):
1. SSH into the S3 and login
2. Issue the following commands sequentially.
a) cd /usr/bin
b) mv cgminer cgminer.4_6
c) mv cgminer.bak cgminer
d) reboot
------ END DEPRECATED! ------UPDATE: - upgrade to cgminer 4.6.1 - 10th Oct 2014A further update to cgminer, aka version 4.6.1, was posted by ckolivas (
https://bitcointalk.org/index.php?topic=671189.msg9134744#msg9134744) and being the ever inquisitive type I decided to install it on one of my S3+'s.
But first, an update to the previous version 4.6.0 which I had installed then removed due to the "apparent" drop in hashing speed. In the interim, I obtained a couple of S1 upgrade kits from bitmain (when they were still available) and upgraded a few of my S1's. The process required me to flash the now upgraded S1's with the S3+ firmware which I did, and I additionally installed cgminer 4.6.0 onto them. When I ran the upgrades, they were hashing marginally faster than my factory S3's and so I decided to upgrade the firmware on my S3's to the latest one AND install cgminer 4.6.0 and to my delight, the previously observed speed drop was no where!
Moving on, when the new update to cgminer was published, I installed it on both my upgraded (now) S3's and the factory S3's. In the announcement post, ckolivas mentions that version 4.6.1 does improve hashing speed to begin with, but overall it does not improve / increase the hashing speed. My observations are:
1. Hashing is more stable and gets up to speed quicker.
2. I have been hashing on slush which sets diff dynamically, and with version 4.6.1 my diff is set accurately quicker and remains stable for longer. Of course, I have only had this running for a few days.
3. On my machines, they are hashing marginally faster (and higher) than I have seen them before! So, I am happy to contradict the software author's opinion here.
Finally, to install cgminer version 4.6.1, the process is the same as before with only the file changing, i.e
Issue the following commands sequentially.
a) cd /usr/bin
b) mv cgminer cgminer.bak
c) wget
http://ck.kolivas.org/apps/cgminer/antminer/s3/4.6.1-141020/cgminer d) chmod +x cgminer
e) reboot
EDIT: cgminer 4.6.1-141009 now deprecated and un-available-
http://ck.kolivas.org/apps/cgminer/antminer/s3/4.6.1-141009/cgminerI'd recomend ensuring the S3 as the latest firmware if you want to install over the stock cgminer, however, it will run without the firmware update too.
UPDATE: - Adding frequencies to the latest firmware 21st Oct 2014The stock firmware for the S3+ contains frequencies up to 250M, and should you want to overclock over that, you'll need to manually add the frequency. A guide for that can be found in the thread linked via:
https://bitcointalk.org/index.php?topic=699064.msg8370071#msg8370071UPDATE: - New S3+ Firmware released by bitmain 25th October 2014Bitmain released a new firmware for the S3+ that now includes version 4.6.1 of cgminer. Unfortunately the firmware, at the time of writing this, contains an error which makes it impossible to update the miner configuration. There is a fix for this:
1. Download and flash firmware from:
https://bitmaintech.com/support.htm?pid=007201407180243004432lBQW28O06332. When the rig reboots, SSH into the S3 and login (remember if you chose not to keep settings while flashing, it will pop up on the default IP of 192.168.1.99 rather than its previous IP).
3. Enter this and press enter:
sed -i 's/Save\&Apply/Save\&Apply/g' /usr/lib/lua/luci/model/cbi/cgminer/cgminer.luaYou can now browse to the miner configuration page and apply any changes. Also remember to change your network back to DHCP client as the firmware resets it to Static.
If this has been useful and you'd like to donate some BTC, please send to:
1AwgqD7A2KuQ4WT4273JXZPUf29BAbdp2or point you rig for your chosen amount of minutes (or days !
) to:
stratum+tcp://stratum.bitcoin.cz:3333 with the user
pekatete and password
xUPDATE: 20th December 2014 - Freq 275 voltage setting 0815, timeout 14 overclockSince the release of the firmware that allowed to set voltage, I have found another sweet spot for the S3+ at a frequency of 275. I had to reduce the timeout from that suggested in some posts on this forum to be able to get a reasonable HW error rate. I ended up with the following setting in the respective file:
pb:value("14:275:0a82", translate("275M")) which translates into timeout: 14, frequency: 275, register value: 0a82. The voltage setting I used is: 0815 (see also the voltage OC thread I posted here:
https://bitcointalk.org/index.php?topic=883197)
And after approx 24 hrs ....
And the poolside after approx 24 hrs ....
