GridSeed 5-chip USB miner voltage mod

[Jess85]

So for all those countless requests for a clear step by step guide that have gone unanswered...

I am happy to inform you that..

A step by step guide with HD images has been released on Bitcointalk Go.

[Cablez]

So for all those countless requests for a clear step by step guide that have gone unanswered...

I am happy to inform you that..

A step by step guide with HD images has been released on Bitcointalk Go.

That is a good guide.  Well done.

[gtraah]

So for all those countless requests for a clear step by step guide that have gone unanswered...

I am happy to inform you that..

A step by step guide with HD images has been released on Bitcointalk Go.

AWESOME WORK JESS- THANK YOU FINALLY

Also have you heard of Vmod4?

Check this out these guys are doing it they state Less than 5HW errors per day at 1250 Stable and they are selling there seeds like this

https://www.sevengnomes.com/index.php/asics/modded-gridseed.html

I wonder if Vmod4 is just a higher kohm resistor?

You know how you mention the 47k resistor? Well the 49.9k is what I am getting and many are able to run 1200 stable at 510-513Kh less than <5hw per 24hr

[Jess85]

So for all those countless requests for a clear step by step guide that have gone unanswered...

I am happy to inform you that..

A step by step guide with HD images has been released on Bitcointalk Go.

AWESOME WORK JESS- THANK YOU FINALLY

Also have you heard of Vmod4?

Check this out these guys are doing it they state Less than 5HW errors per day at 1250 Stable and they are selling there seeds like this

https://www.sevengnomes.com/index.php/asics/modded-gridseed.html

I wonder if Vmod4 is just a higher kohm resistor?

You know how you mention the 47k resistor? Well the 49.9k is what I am getting and many are able to run 1200 stable at 510-513Kh less than <5hw per 24hr

It is a higher resistor, but if you go any higher than 49.9k it is necessary to treat the devices with further mods to increase the efficiency and lifespan of the device. A coolant application is listed in the service description as one of these mods. There is more that can be done and I will clear this up with Seven Gnomes management. There is no use running them faster if it dies within a month.

Edit: It appears more was already being done to increase the efficiency and lifespan of the device, I spoke to management, it is now also listed on their service page.

[nst6563]

My oldest pod has this part:

*image snipped*

All my newer pods have this part:

*image snipped*

All have STM com chip.

Is it a capacitor?  Would someone please explain what is the difference in the parts.  You can tell I don't understand this stuff at all.  Would the difference in parts affect the volt mod in anyway?
The oldest pod runs warmer.  

Edit: I have not done any mods.

That is a capacitor.  I wonder why they would decrease the value on the newer pods....and if that has anything to do with why they are reportedly "less stable" than the older pods at higher speeds.

I've also noticed in some pictures in this thread that one of the 3 mosfets is missing.  

That is an interesting observation. And, if the missing FET is or was working in parallel with the other two, it would almost seem to be  intentional or perhaps sacrificed to save money on production costs. A single part makes a big difference on the books, hence, bottom line.
It is also a weak spot electrically and can possibly add switching (although very high frequency) noise to that side of the system. Perhaps too, quiescent current demands are not at very high demand - to justify the extra components and, that would explain the difference in capacitance of the Electrolytic Capacitor.
Just a guess....

I believe (if I remember correctly) that the mosfet was missing from an older pod that had the larger LED's.  I have a newer pod with SMT LED's and it has 3 mosfets.  Not sure what the difference would be.  I'll see if I can find the picture of the pod that was missing the 3rd mosfet.  It was towards the beginning of this thread.

Found it:  https://bitcointalk.org/index.php?topic=519112.msg5901237#msg5901237 
Post 289.

[happydaze]

Right now I only have the one running at 1225Mhz.  I have another one coming in a few days which I haven't fully decided if I want to just do the bridge and dual mine, or do the resistor swap and only scrypt mine.  I'll definitely mill out that part of the heatsink so it makes full contact with all 5 of the gc3355 chips though.

If you try the bridge mod and dual mining please let me know.  I have to make that decision too. I've been dual mining for a few weeks now and like the idea of it.  With dual mining I've found the frequency is set and controlled by cgminer.  Setting a different frequency in cpuminer has no effect at all when dual mining that I can tell.  Max stable frequency dual mining for me is 750MHz.  I was thinking maybe 800MHz or 850MHz could be possible with the bridge mod.  50MHz increments up to 900MHz in cgminer 3.8.5 for Gridseeds from what I see in the code.

I practiced soldering on a scrap board today and it went well.  It's easier when there's no pressure, nothing to mess up.  I'm really not good at soldering but all tips mentioned here by the pros really helped.

Practice on scrap:


As mentioned many times in this topic and in Jesse's Official Overclocking (voltmod) Guide For Gridseeds use flux.  The solder flows in to replace the flux like magic.  I know I can do and undue volt mod 1.  I should be able to do volt mod 3 but I'm not sure if I could undue it in case I wanted to go back to dual mining. I'd really like to know how much we can get out of these while dual mining.

[mintyfresh]

Finished my first mod and it wasn't as bad as I thought.  Miner working and has no HW errors and no rejects since I swapped in the 49.9k resistor.  Testing with an updated Scripta image now to see how fast she'll go without errors and will update.

What's the power draw with the 49.9k resistor mod? 

Still okay to make the fan (quiet please!) mod as well?

Cheers!

[nst6563]

Right now I only have the one running at 1225Mhz.  I have another one coming in a few days which I haven't fully decided if I want to just do the bridge and dual mine, or do the resistor swap and only scrypt mine.  I'll definitely mill out that part of the heatsink so it makes full contact with all 5 of the gc3355 chips though.

If you try the bridge mod and dual mining please let me know.  I have to make that decision too. I've been dual mining for a few weeks now and like the idea of it.  With dual mining I've found the frequency is set and controlled by cgminer.  Setting a different frequency in cpuminer has no effect at all when dual mining that I can tell.  Max stable frequency dual mining for me is 750MHz.  I was thinking maybe 800MHz or 850MHz could be possible with the bridge mod.  50MHz increments up to 900MHz in cgminer 3.8.5 for Gridseeds from what I see in the code.

I practiced soldering on a scrap board today and it went well.  It's easier when there's no pressure, nothing to mess up.  I'm really not good at soldering but all tips mentioned here by the pros really helped.

Practice on scrap:


As mentioned many times in this topic and in Jesse's Official Overclocking (voltmod) Guide For Gridseeds use flux.  The solder flows in to replace the flux like magic.  I know I can do and undue volt mod 1.  I should be able to do volt mod 3 but I'm not sure if I could undue it in case I wanted to go back to dual mining. I'd really like to know how much we can get out of these while dual mining.

Here's the idea I had....and right now it's just an idea...
Do the single bridge mod so that you can activate the higher voltage by using the switch voltage=1 in the gridseed options.  Then change the resistor that corresponds to that VID setting (which should be the 36k as referenced here https://bitcointalk.org/index.php?topic=519112.msg5767028#msg5767028 on post #33) to the higher value you're looking for (47.7k or 49.9k or even maybe higher).

Then, should you wish to run stock voltage, you simply leave out the voltage=1 parameter.  If you wish to mine scrypt only with increased hashrates, specify the voltage=1 parameter and the higher clockspeed.

[mintyfresh]

Finished my first mod and it wasn't as bad as I thought.  Miner working and has no HW errors and no rejects since I swapped in the 49.9k resistor.  Testing with an updated Scripta image now to see how fast she'll go without errors and will update.

What's the power draw with the 49.9k resistor mod? 

Still okay to make the fan (quiet please!) mod as well?

1200 MHz - Rock steady at 508kh/s with no HW errors the last hour.  Letting it run overnight and then I'm modding my other 9 miners tomorrow. 49.9k 1% FTW!

[happydaze]

Here's the idea I had....and right now it's just an idea...
Do the single bridge mod so that you can activate the higher voltage by using the switch voltage=1 in the gridseed options.  Then change the resistor that corresponds to that VID setting (which should be the 36k as referenced here https://bitcointalk.org/index.php?topic=519112.msg5767028#msg5767028 on post #33) to the higher value you're looking for (47.7k or 49.9k or even maybe higher).

Then, should you wish to run stock voltage, you simply leave out the voltage=1 parameter.  If you wish to mine scrypt only with increased hashrates, specify the voltage=1 parameter and the higher clockspeed.

I don't know if the voltage option is in cgminer 3.8.5.   I don't know programming but I did read through the gridseed driver code in cgminer 3.8.5 and don't see any reference to voltage options.  I see voltage options in cgminer 3.7.2 gridseed drivers but I don't think that is meant for dual mode mining.

[gtraah]

Yeah, Wolfey2014 came up with that value after doing his own tests on the mods that some other ingenious people came up with.
49.9k is exactly what my miners have in them and they are all rock stable at 1188 to 1250KHs! Very few if any HW errors! The usual failed nonce occurs regularly in any case. All miners do this. It's not a bug, just a part of the checks and balances our systems keep track of.

My miners are all stably ON all the time too. No drop outs or nothing for weeks since I modified them. Set and forget. They just make money for me 24/7! All I gotta do is check my balances every once in a while.
By the way, they are all using the same heat sink pad they came with. Screws were all torqued evenly.
Comm port FIFO buffers (if your program uses them) are not needed. Turn them OFF!
Just the way Wolfey told me to set it up.  

I heard of these fifo buffers but not sure where this is.. i am using cgminer and all i did with zadig is replace the usb with the winusb driver once... now everytime i plug the seeds in it automatically goes under usb in device manager and Thats it.. should i also do the fifo buffer thing? If so where do i go to find this setting and is there someone constantly updating cgminer where is the place to find the latest modified version...not sure if i have it or not... i dont understand why i remember ppl having to restart the miners every 24 hrs.. i have been tweaking and testing mine ao i have not set and forget it yet but because of that i may have not needed to restart the miners.. can someone tell me when i start to set and forget it am i goin have to restart every 24 hrs with cgminer?

[gtraah]

Here's the idea I had....and right now it's just an idea...
Do the single bridge mod so that you can activate the higher voltage by using the switch voltage=1 in the gridseed options.  Then change the resistor that corresponds to that VID setting (which should be the 36k as referenced here https://bitcointalk.org/index.php?topic=519112.msg5767028#msg5767028 on post #33) to the higher value you're looking for (47.7k or 49.9k or even maybe higher).

Then, should you wish to run stock voltage, you simply leave out the voltage=1 parameter.  If you wish to mine scrypt only with increased hashrates, specify the voltage=1 parameter and the higher clockspeed.

Dude this idea in theory is sick! If this works then basically this gives people the option to run in scrypt only mode at 510-515kh

And then with a simple switch they can go back to dual mining... fantastic !! Best of both worlds.. has anyone tried this? This would be vmod5 if it works someone who is a pro at soldering should test this so they can easily revert back if it doesn't work.. this would be great for the community and for people with 100+ seeds that is a potential 1TH of btc mining power available at the flick of a switch

[nst6563]

So where on this gridseed do I find the measurement point for the voltage?

Just for the hell of it and since I couldn't sleep, I did the bridge mod, then wired up a 50k pot to the 36K resistor that corresponds to VID1 (Voltage = 1 parameter) and a 50K pot to the 33K which corresponds to VID0.  Since I know someone may ask...I removed the stock resistors.  I set them both to stock resistances and noticed some odd behavior.  At 800Mhz it seemed that without the Voltage=1 parameter the pod would hash away, get no accepted shares, and accumulate hw errors.  At the same 800Mhz speed using the voltage=1 parameter the pod would hash away, get accepted shares, and still accumulate some hw errors.  Not as many as without the voltage=1 parameter, but still errors all the same.  


It could be that my pod is just going to throw hw errors due to some damage when the mosfet blew...so someone else may need to give the idea a shot and see how it turns out.

*edit*  - yep...even with the 2 50k pots set to the stock gridseed values of 33k and 36k, and the clock speed dropped back to 800Mhz it generates errors at a frequency of about 1 per minute.  Client side hashrate shows ~350kh/s but poolside shows around 327kh/s. 

[Ranma13]

I've done the voltage mod with 49.9kohm resistors and the 5V fan mod on 8 of my Gridseeds, but I'm having a problem. I'm using the Hashra image with a Raspberry Pi, but the Gridseeds are only stable up to 950 MHz. What's weird is, they run perfectly fine at 950 MHz, but the moment I try bumping it up to 1000 MHz, they basically fail to hash at all. To give an idea, at 950 MHz, my pool reports ~3.5 MH/s with about a 3-5% reject rate. At 1000 MHz, my pool reports ~0.01 MH/s with a 80-90% reject rate. Any idea what could be causing the problem?

[gtraah]

So where on this gridseed do I find the measurement point for the voltage?

Just for the hell of it and since I couldn't sleep, I did the bridge mod, then wired up a 50k pot to the 36K resistor that corresponds to VID1 (Voltage = 1 parameter) and a 50K pot to the 33K which corresponds to VID0.  Since I know someone may ask...I removed the stock resistors.  I set them both to stock resistances and noticed some odd behavior.  At 800Mhz it seemed that without the Voltage=1 parameter the pod would hash away, get no accepted shares, and accumulate hw errors.  At the same 800Mhz speed using the voltage=1 parameter the pod would hash away, get accepted shares, and still accumulate some hw errors.  Not as many as without the voltage=1 parameter, but still errors all the same.  


It could be that my pod is just going to throw hw errors due to some damage when the mosfet blew...so someone else may need to give the idea a shot and see how it turns out.

*edit*  - yep...even with the 2 50k pots set to the stock gridseed values of 33k and 36k, and the clock speed dropped back to 800Mhz it generates errors at a frequency of about 1 per minute.  Client side hashrate shows ~350kh/s but poolside shows around 327kh/s. 

Hmmm yeh i know what you mean , its hard to tell if its the mods fault or its just your stuffed up mofset Grid, hmmm I am still waiting on all my accesories to start modding. someone with awesome soldering skills would most likely have fun trying this , hopefully someone does as this will give me an idea - I beleive having a mod that allows you to choose if you want higher voltage or not would be the most ideal mod of them all. This means you do not ever have to revert back to normal all you need to do is flick the switch and boom your back to stock mode

[nst6563]

So where on this gridseed do I find the measurement point for the voltage?

Just for the hell of it and since I couldn't sleep, I did the bridge mod, then wired up a 50k pot to the 36K resistor that corresponds to VID1 (Voltage = 1 parameter) and a 50K pot to the 33K which corresponds to VID0.  Since I know someone may ask...I removed the stock resistors.  I set them both to stock resistances and noticed some odd behavior.  At 800Mhz it seemed that without the Voltage=1 parameter the pod would hash away, get no accepted shares, and accumulate hw errors.  At the same 800Mhz speed using the voltage=1 parameter the pod would hash away, get accepted shares, and still accumulate some hw errors.  Not as many as without the voltage=1 parameter, but still errors all the same.  


It could be that my pod is just going to throw hw errors due to some damage when the mosfet blew...so someone else may need to give the idea a shot and see how it turns out.

*edit*  - yep...even with the 2 50k pots set to the stock gridseed values of 33k and 36k, and the clock speed dropped back to 800Mhz it generates errors at a frequency of about 1 per minute.  Client side hashrate shows ~350kh/s but poolside shows around 327kh/s. 

Hmmm yeh i know what you mean , its hard to tell if its the mods fault or its just your stuffed up mofset Grid, hmmm I am still waiting on all my accesories to start modding. someone with awesome soldering skills would most likely have fun trying this , hopefully someone does as this will give me an idea - I beleive having a mod that allows you to choose if you want higher voltage or not would be the most ideal mod of them all. This means you do not ever have to revert back to normal all you need to do is flick the switch and boom your back to stock mode

Actually...if you REALLY wanted to just "flick a switch", you could wire up a 3-way switch with the resistance values you wanted, and mount the switch to the side of the gridseed (I stuck my 50k pots to the side of the fan and used the shortest wires I could) and label it.  That way POS1 = stock, POS2=mod.

The way mine is, I just unplug the gridseed and adjust the 50k pots.

[gtraah]

So where on this gridseed do I find the measurement point for the voltage?

Just for the hell of it and since I couldn't sleep, I did the bridge mod, then wired up a 50k pot to the 36K resistor that corresponds to VID1 (Voltage = 1 parameter) and a 50K pot to the 33K which corresponds to VID0.  Since I know someone may ask...I removed the stock resistors.  I set them both to stock resistances and noticed some odd behavior.  At 800Mhz it seemed that without the Voltage=1 parameter the pod would hash away, get no accepted shares, and accumulate hw errors.  At the same 800Mhz speed using the voltage=1 parameter the pod would hash away, get accepted shares, and still accumulate some hw errors.  Not as many as without the voltage=1 parameter, but still errors all the same.  


It could be that my pod is just going to throw hw errors due to some damage when the mosfet blew...so someone else may need to give the idea a shot and see how it turns out.

*edit*  - yep...even with the 2 50k pots set to the stock gridseed values of 33k and 36k, and the clock speed dropped back to 800Mhz it generates errors at a frequency of about 1 per minute.  Client side hashrate shows ~350kh/s but poolside shows around 327kh/s.  

Hmmm yeh i know what you mean , its hard to tell if its the mods fault or its just your stuffed up mofset Grid, hmmm I am still waiting on all my accesories to start modding. someone with awesome soldering skills would most likely have fun trying this , hopefully someone does as this will give me an idea - I beleive having a mod that allows you to choose if you want higher voltage or not would be the most ideal mod of them all. This means you do not ever have to revert back to normal all you need to do is flick the switch and boom your back to stock mode

Actually...if you REALLY wanted to just "flick a switch", you could wire up a 3-way switch with the resistance values you wanted, and mount the switch to the side of the gridseed (I stuck my 50k pots to the side of the fan and used the shortest wires I could) and label it.  That way POS1 = stock, POS2=mod.

The way mine is, I just unplug the gridseed and adjust the 50k pots.

Sorry I am not understanding pots? is that just resistor? Also Are we talking about this is based on Vmod3 right? I was thinking of Software switch but again, u said another good idea "physical switch" , 2 Wires on the 2 contacts in replace of the R52 resistor and those 2 wires lead you to maybe 4 different resistor with a 4 way switch hhaha.. Stock Mode - 47K Mode - 49.9K mode and then 52K mode

BOOOM we now have SuperVmod- Giving us the choice to Dual mine, BTC mine, Scrypt Mine, + Scrypt mine OC in 3 OC steps.  

Since I am not a electronic guy even though I have soldered a few chips and leds on mobile phones back in the Nokia phone days.. I would need detailed instructions to even attempt this. Also seems like it would be an AWESOME mod but seems like alot of shit that needs to be done... Which is why I initially thought, By doing the Jumper/short mod + changing over 1 resistor to the perfect Kohm amount.. then enables us to flick the swtich with software. Both are awesome ideas if they work , The Physical switch is a definite one that will work but = Harder to do... The Software/hardware mod is easier but Not 100% it will work.

I was looking at these miners and I thought of something to save room,

I was thinking of pulling apart 2 x Gridseeds and removing the fan on one, somehow attaching the heatsink without the fan to the bottom of the other gridseed with the fan , 1 fan is pretty powerfull, this saves us doing the 5v fan mod as now you are only using the 1 fan for 2, so bascially cuts the fan power in half. And ALSO saves room as you have basically mashed 2x grids together and giving the cooling from the 1 fan. WIth the mod this will make 1 double whopper grid with 10 Chips= 1000Kh +  

Something like this >>> https://www.dropbox.com/s/gaykii3dlqvqfjc/mashhh.jpg

Edit:
even better!!>>> I just thought of making it smaller by removing the sink directly under fan in the photo and having the back against one of the boards This makes it smaller  by only having 3 peices of sinks and the fan, like this >>> https://www.dropbox.com/s/8q278fnjgzd18hj/mash2.png - and maybe cooler as the fan is now closer to both boards. Not bad looking for a future 1000Kh little beast

[nst6563]

*SNIP*

Sorry I am not understanding pots? is that just resistor? Also Are we talking about this is based on Vmod3 right? I was thinking of Software switch but again, u said another good idea "physical switch" , 2 Wires on the 2 contacts in replace of the R52 resistor and those 2 wires lead you to maybe 4 different resistor with a 4 way switch hhaha.. Stock Mode - 47K Mode - 49.9K mode and then 52K mode

BOOOM we now have SuperVmod- Giving us the choice to Dual mine, BTC mine, Scrypt Mine, + Scrypt mine OC in 3 OC steps.  

Since I am not a electronic guy even though I have soldered a few chips and leds on mobile phones back in the Nokia phone days.. I would need detailed instructions to even attempt this. Also seems like it would be an AWESOME mod but seems like alot of shit that needs to be done... Which is why I initially thought, By doing the Jumper/short mod + changing over 1 resistor to the perfect Kohm amount.. then enables us to flick the swtich with software. Both are awesome ideas if they work , The Physical switch is a definite one that will work but = Harder to do... The Software/hardware mod is easier but Not 100% it will work.

I was looking at these miners and I thought of something to save room,

I was thinking of pulling apart 2 x Gridseeds and removing the fan on one, somehow attaching the heatsink without the fan to the bottom of the other gridseed with the fan , 1 fan is pretty powerfull, this saves us doing the 5v fan mod as now you are only using the 1 fan for 2, so bascially cuts the fan power in half. And ALSO saves room as you have basically mashed 2x grids together and giving the cooling from the 1 fan. WIth the mod this will make 1 double whopper grid with 10 Chips= 1000Kh +  

Something like this >>> https://www.dropbox.com/s/gaykii3dlqvqfjc/mashhh.jpg

Edit:
even better!!>>> I just thought of making it smaller by removing the sink directly under fan in the photo and having the back against one of the boards This makes it smaller  by only having 3 peices of sinks and the fan, like this >>> https://www.dropbox.com/s/8q278fnjgzd18hj/mash2.png - and maybe cooler as the fan is now closer to both boards. Not bad looking for a future 1000Kh little beast

Yes, pot is short for Potentiometer which is a variable resistor.  If I had 50k worth of "pot" I wouldn't be concerned about modding a gridseed

The physical switch is definitely possible.  It wouldn't really be all that hard either I don't think.  The software parameter is the real interesting one I think. 

[mintyfresh]

I've done the voltage mod with 49.9kohm resistors and the 5V fan mod on 8 of my Gridseeds, but I'm having a problem. I'm using the Hashra image with a Raspberry Pi, but the Gridseeds are only stable up to 950 MHz. What's weird is, they run perfectly fine at 950 MHz, but the moment I try bumping it up to 1000 MHz, they basically fail to hash at all. To give an idea, at 950 MHz, my pool reports ~3.5 MH/s with about a 3-5% reject rate. At 1000 MHz, my pool reports ~0.01 MH/s with a 80-90% reject rate. Any idea what could be causing the problem?

Try this image: https://github.com/mox235/scripta

There is a link to an image in the readme.  I modded all 10 of mine and they are running at 1200Mhz with 0 rejects and 0 hardware errors.  I forked that repo and will be doing some work on that image to make it even better.

It uses a custom cgminer that supports frequencies for each miner so you can tune your rig.

[happydaze]

I think the gridseed could possibly handle the first mod (bridge + voltage=1 in command line) to reach 1000Mhz and dual mine.  I don't think I'd push it farther than that though.  I tried the dual mining mode on mine with the resistor mod.  The Ubiq m3022m mosfet on mine blew the instant dual mining kicked in.  That part is a real bugger to find in the US, but luckily I was able to cross-reference a part from TI (CSD17552Q5A N-Ch 30v mosfet) that met most of the original specs and it's back up and running now at the 1225Mhz scrypt only.

As far as I know, I'm not getting .1ltc a day either, just a little less actually.  I've been using Clevermining and just switched to Multipool to try them out since they have Cryptsy integration.  In the past 15 days I've gotten 0.02552966 BTC from Clevermining.  I only have the single gridseed plus an nvidia gtx 560se (98kh/s).  My ati card bit the dust unfortunately.

I did full vmod 1 on one gridseed and am testing dual mode now.  Cgminer in BTC mode seems to handle 1000Mhz.  I did not test 1000Mhz long though as I wanted dual mode results.  I have to clock everything down to 850Mhz to get cpuminer happily mining LTC at the same time.  900Mhz was too high for cpuminer.  Cgminer 3.8.5 has 50Mhz frequency increases so maybe 875Mhz would work but it is not in the options.  Everything looks stable at 850Mhz in dual mode with vmod 1 in place. 

Preliminary results indicate 9.5 Ghash BTC and 350 Khash LTC poolside.  That puts the performance right in between vmod 3 @ 500 khash single mode and vmod 1 @ 400 khash single mode.  I calculate (for me) that vmod1 dual would give 12% lower performance than vmod 3 and that vmod1 dual would give 11% higher performance than vmod 1 single.  That's all based on today's difficulty and prices and my power costs.

66 watts power consumption - to anyone who really understands this stuff; do I need to concerned about that?  Will it shorten the life of the gridseed?  That's approx 1 amp more than dual mode with no voltage mod (my other gridseeds).