I noticed there are two pictures of mods, and I was wondering if someone can explain the difference
- - First mod in first post, single short between the two points in the green box, user modified cgminer, and voltage=1 (and freq to 950+)
- - Second page has the same picture, with two parts circled (two pairs to short out).
What is the difference between shorting just one pair, vs both pairs?
I am running the modified cgminer (at freq=888 now and stable @ 376kh ~ 20HW errors /day), hanging off a RaspberryPi for the controller. Would soldering just the first pair work in this case?
Thanks again for posting these mods!
I was going to wait until tomorrow but what the heck....
I decided a couple days ago to go ahead and try modding one of my pods.
I made the first mod which is to jump the two resistors as shown with the yellow stripes. Done deal.
I got a bit better performance out of it @ 900MHz and 950Mhz but still pulled a red nonce every once in a while and at times they would fill the window (cpuminer) for a short birst then go away.
I thought "how strange, what is causing this? Could it be a timing issue?"
Bingo!
The guy who did the mods and had his GS5 running at between 1000 and 1100MHz stable but with a few red nonce's gave me the tip...
I thought, let me try the pencil mod.
So I tried lowering the PLL voltage first to around 1.01V. Seemed to stabilize running at 950MHz so well that I only saw a red nonce every great once in a while over an hour or so of operation where before it was about 3 times as much.
Okay, so changing the resistor was next.
I changed out the 36K for a 38K 5% resistor.
BINGO!
Now I have stable 'no red nonce' operation at 1000MHz!... It's been running stably for over an hour now with ZERO red nonce's! Perfect!
I'm going to let it run overnight and see how things are in the morning. I have a good feeling this is the trick I was looking for.
Thanks to the author of this mod!
I'll save further congrats for later on if I see stable operation over time.
Oh and one other thing. I decided to go ahead and test my theory that lowering the voltage of the cooling fan to 5V was not a good idea due to the usual problems associated with magnetic DC motors.
I guess the drive electronics of DC fan motors has come a long way since I last farted around with them years ago.
I'm driving it with 5V now without any problems so far. Runs just fast enough to keep air moving at a good enough rate to keep the unit cool to the touch! I mean below 90*F. More like 79^ to 81* currently.
And man, it is quiet! Music to my ears! The pod was cooking at 115 to 120*F at 1000MHz which is understandable. That's crankin, for this little bugger!
Not running hotter or pulling more current like I thought it would, at all.
Sorry for scaring some of you guys out of trying it but I guess I get to make up for it by risking burning up my fan etc.
I'll let you know how that went overnight too.
I will also attempt to run it off of the 5V USB power next and see if it screws anything up comm wise or power wise.
It's pulling less than 75mA running. Pulls 140mA start up for a quick second before it calms back down.
I think it would be easy enough for most folks who end up doing this mod, provided mine works out okay, will be able to compensate for the additional load it puts on USB power. But it's a short cut method I really don't recommend in general. One should use a voltage regulator to drop from 12V to 5V. There is more headroom on that rail too in most cases.
Wish me luck!
Wolfey2014