Quote from: romang on March 24, 2014, 04:52:15 AM

Quote from: darkfriend77 on March 23, 2014, 05:26:49 PM

side view on the rack ... 20 gridseeds, 1 raspberry, 2 usb hubs ... everything powered by the atx psu ..

Love it!

Hey, just a heads up you guys, from the gridseed voltage mod thread... Enjoy!
Nice rig darkfriend! Well done!

Quote from: sandor111 on March 21, 2014, 02:35:57 AM

Quote from: wolfey2014 on March 21, 2014, 01:54:30 AM

Quote from: sandor111 on March 20, 2014, 01:53:52 PM

I am giving out 0.6BTC to the first to get his Gridseed miner stable at 1100 MHz (<10 HW error in 24h) and post the steps to mod the miner. So far I have managed to get it stable at 1013 MHz, but I feel we can push it further.
I have found the only way to push these further is by replacing the 36k resistor with a higher one and playing with PLL voltage, you need to lower the resistance of R211 or R212 by tracing it with a pencil. Measure the voltage across both resistors and it should be around 1.1v total. If you want to increase PLL voltage, trace R212, to decrease it, trace R211 (go back and forth atleast 10-20 times or you will not notice a change). Simply use an eraser to revert the mod. Personally 1.05v seems sweet spot.

Disclaimer: as always, I am not responsible for damage to your miner, do this at your own risk!

What is the test point on the card for checking/monitoring the voltage?

Thanks
Wolfey2014

Core voltage can be measured across the 36k, assuming it's voltmodded (by default it would be the 33k)
PLL voltage can be measured across R211 and R212.

Hello Sandor.
I made the modifications to 2 of my GS5 USB's.
Both jumpers done.
38k @ 5% resistor added in place of the original. I used a 1/8W linear type.
Pencil traced R112 to lower PLL voltage to 1.018 or so -virtually zero red nonce's.
I've never used the pencil trick before. Amazingly effective. Just hope its permanent.
1.05 seemed to high as it still got some red nonce's.
Both GS5's are rock steady for over 40 hours now. No problems at all.

They run sufficiently warm enough now that I put the fan back on them but am running them off the 5V USB with good results. Only pulling about 78mA. 140mA surge at start up but it lasts less than 2 seconds. They are whisper quiet and provide enough air volume to keep them nice and room temp cool. They were running at nearly 118*F fanless as expected after the mods.
I'm sure they can run hotter than that without problems but I also didn't want to just let the fans go to waste Wink

I'm very pleased with their stable performance at 1000MHz!
Running it solo, I'm seeing nearly 600KH's out of it at the pool. Wink

NICE!

So, what's next? How do we squeeze more performance out of them? Any ideas?
I'm game!

Peace!
Wolfey2014