Topic: GRIDSEED G-BLADE Overclocking 7Mh/s, improvements and repair - page 6. (Read 74130 times)

one and most important things people forget when moding devices, what happends when fans stops?
It will frie your device in fev seconds so add fev thermal switches which will stop device before it is fried.

As I said those 2% winners are now, who sell mining devices, why do you think there is day after day more producers of that?
And buyers of that devices makes coins go arround and have a value.
In those 2% are also those people which buy at low and sell at high.
The rest will at the end have alot of these devices and no litecoins or bitcoins. That is mathematically proven.

These are like the ones that I got, listed on Fleebay.
http://www.ebay.com/itm/111039995473?_trksid=p2060778.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

My mosfet chip heatsink (one glued to all three tops) is a 19x19mm parts.
It will not fit due to the board mounted fan power connector and the plug so
I removed and soldered the main fan wires directly to the circuit board to
allow for clearance.

The window for retards has closed, it's now a multi-faceted game...
You have to pick/launch coins, mine, start/catch pumps, and arb exchanges in a professional manner...
And, especially, limit counterparty risk.

It's now a classic Zero Sum Game = 2% winners...
The other 98% will be selling paperweights for $0.30 on the dollar with no takers.

On the other hand, as just a hobby... you could do worse.

This one is perfect , i don´t found this size on local shops but i made similar ones on my own
Good idea! Nice!

It´s interesting to do some tunning on this parts , but now they "eat" more money , some heatsinks here some resistors there .... but take this as learning lesson , i don´t know if the additional 1 - 2 MHS will cover the costs and the time spend ever. Not only "just for fun" i hope...

VEV227M035S0ANB01K load time 2000 h

http://www.voelkner.de/products/423295/Elektrolyt-Kondensator-SMD-220-F-35-V-20-x-H-10-mm-x-10.2-mm-VEV227M035S0ANB01K-1-St..html

http://i60.tinypic.com/zv1u2s.jpg

Or this one from Mouser PCR1V221MCL1GS loadtime 4000h it´s a little bit smaller but fits also.
http://de.mouser.com/Search/ProductDetail.aspx?R=PCR1V221MCL1GSvirtualkey64700000virtualkey647-PCR1V221MCL1GS

And there are 2 Big solder pads , so if there are a little diferences , no problem. Maybe consider to buy some desoldering wire , it makes things easier.

And here what the Datasheet says about the soldering:

Freeman and Race-

Thanks for the advice!  I do have another question:

          1) What is the part number for the 220uF, 35V capacitor? 

I could do a search, but the part has to have a compatible mounting surface.  I am not so sure of how to read the catalogs.

I did order a variety of heatsinks.  The Gridseed GC3355 chips are 6.1mm x 6.1mm square, and i bought 6x6mm sq. base heatsinks with adhesive bases.  I also found 45mm x 75mm x 20mm (fin height) heatsinks for the back of the circuit board under the hot components, and i have sheets of thin, double-stick thermal-conductive film that I can cut to fit.  The large heatsinks just fit the area on the back of the board within a narrow margin; so no modifications are required to avoid shorts.  I bought a few other small, adhesive heatsinks for the hot-spot components.

I also bought a 120mm fan and a step-down adapter to fit the case.  I may also add 40mm sq. fans on the large heatsinks, and plug them into the unused 2-pin power socket on the gridseed.

The parts are coming from Hong Kong, so I have a couple weeks wait ahead.  I am considering purchasing a decent hot-air rework station just to have it on hand.  There are several modding projects I have in mind besides my Gridseed.         -Scryptr

Again I highly recommend to add a fan for the backside, even if you use a Nothbridge heatsink with active cooling. You have to realize a serious arifolw backwards , not only for the mosfets, the cap and the choke generates a lot of heat , too. And not to forget the power terminal , i still use the default ones , but i replace them two times so far, even if i have a backfan , the plastic isolation in the plug simply melt after a while. So its much,  much better to use screw terminals or to solder the powerstripes direcltly on pcb.
The guys from gridseed seems just to finsh the device , but only with time and money aspect , the quality was not so important for them it seems. We can see that they use absolutley the same power plug as they use for the 5 Chip smaller gridseed, but the power consumption is nearly 2.5 - 3 times greater , if you consider that they calculate the BTC SHA-256 part for the smaller one.And the 5 Chip has a much better cooling because the original fan airfow catch the power plug too.
I think i have to replace the terminals too.This power plugs are maybe good for a IP Cam or something with low power but not for this high temps.

This is what i did (i use Arctic Silent F9 with temp sensor in front and back , they don´t have the same airflow like the original one, but with 2 of them it works good and really silent):

http://i60.tinypic.com/o73o09.jpg
http://i58.tinypic.com/ixd191.jpg
http://i60.tinypic.com/2ilmzbk.jpg
http://i60.tinypic.com/2ug01nk.jpg

I did everything you stated and got around 6.6Mhs @ 963Mhz with variable pot just over 39K
and mosfets heat sink at 139F with difficulty set to 1024 and 230w AC power draw.

I would add if possilble;
-larger heatsink on the mosfets, taller fins then in my photo.
-heatsink with taller fins on back of board or additional fan cooled heat sink. (North Bridge below as others in thread)
http://www.ebay.ca/itm/Logisys-DeepCool-CC2-North-Bridge-2-Chipset-Performance-Compact-Cooler-NEW-/231088748673?pt=US_Memory_Chipset_Cooling&hash=item35cdf67881
-35Vdc Cap replacement is a must
-beads removal and jumper replacement is a must (if no 0 ohm resistors used)

My caps where replaced with a basic soldering iron with a fine tip, did not use my hot air unit
was not that hard to do, exposed side first then pry up a bit while heating but avoid pulling
and tracks off the board surface.

Gridseed Moddermen-

OK, i looked at Freeman's message and checked out the Gridseed Pod modding thread that he referenced.  After reading the Pod thread, it seems that performing BOTH the 33KOhm resistor replacement AND the bridging mod is NOT a good idea.  It may perhaps work, but it is redundant.  Further, the bridging mod requires special software.

So, I look forward to the following:

          1) Place heatsinks on the Gridseed blade, possibly with extra fans.
          2) Replace the 33KOhm resistor with a multi-turn trim pot that has a compatible range.
          3) Change out the 220uF, 16V capacitor with a similar 220uF, 35V capacitor.

This should be enough to run the blade and generate 6+ MegaHash total without excessive heat or damage.  Right now, unmodified, and poolside, I get 5.2-5.5 MegaHash.

I am curious still about how to remove/replace the 220uF capacitor.  Is a hot-air device essential?

Again, thanks for all the technical work made by the contributors to this thread.  -Scryptr

I have calculated, no mather what you buy, you mostly won't get payed off a long time or maybe even never.
I have never payed off my miner and I bought them about 3 months ago and I am not even at half.
Isn't that logical? Why do you think they sell those devices, if minig is more profitable then they will use it by them self not selling it.
But they have calculated and most profitable now is selling that devices and not mining on them.
Because when you buy 500Mhash for alot for alot of money after 3 months they will sell 2THash for the same money and people will buy it and dificulty will raise fast and after 3 months they will sell for the same money 5THash and people will buy it and dificulty will raise again and you didn't payed half of your device after 6 months and dificulty raise more and more.

I am sure profitability is heading south as the overall difficulty is increasing
and the need for more powerful miners are needed at a higher cost.
Kinda of a catch 22 situation, like anything the highest rewards are to those
that take the greatest risk and fork out money for the newest and fastest
miners before release. Only risk what you can afford to loose in mining
hardware and new coin purchases. With the alt coins no limitation in new
coins being released the value of the coins may never be able to generate
profits like previous bitcoin. Also with so many different coins on the market
the hash power is being spread so thin that there might never be enough
prolonged hash power kept on any specific coin to push it up and keep it
there for great profits to be made. The pump and dump in the alt coin market
maybe the only way to make some money. The alt coins of the future might
be no more then old penny stocks. I hope this is not true as my last year
of mining might only be for a few thousand dollars, time will tell and without
adoption of alt coins by the marketplace, countries and businesses the future
might only be very profitable for the coin owners/programmers and miner
hardware manufactures. These are just my own thoughts and conclusions.

But what happens to the profitability , guys 

Anyone see a chance that we have better times in the future? I can´t belive that this can be true , if this continue in this way i don´t  see more than 25% return of my investment , and the rest 75% are gone.

I try to explain... if i´m wrong , someone can correct me please.

Everything what means higher hashrate is like in overclocking any CPU. This means the frequency gives you the maximum number of calculations the chip can do per second.
You can surley try to set higher frequencies whithout any modifications like with the 5 Chip GSD they come with stock freq of 600 Mhz but you can set easily up to 850 Mhz.
Higher frequency means more calculations per second and more Hashrate. The problem is that with higher frequencies the chip becomes unstable and this result in
HW´s or miscalculations. It´s like someone try to do too many things at the same time , and at one point he can´t handle so many opperations and stuck.
So the goal is to get the chips stable at higher frequencies  an they need more Voltage to do this . And of course more voltage and frequency  generates more heat. The second problem.
The default Voltage of the GSD Chips is at 1,2 V With the 33K ohm resistor. If you replace this with a 39 K ohm resistor for example the Voltage rise to 1,4 V , so they
handle more stable frequency but also more heat. This you can easily measure at the big yellow caps.

The bridge voltmod=1 does the same thing but in other way it affects the 2-bit VID convertor to select another output line, this means it selects another resistance. There are 4 Resistors to set 36k, 30k, 33k, and 27k. With the clasic vmode you choose the 36k resistor istead the 33 k , like an overclock jumper without the need to solder any parts.If you do the vmode and choose the 36k , but you replace the 33k resistor , i think the replace of the 33k is useless and do nothing . The convertor coose only one output.
And of course you need the modifed cgminer and set the voltage=1 parameter. So think this is more like an alternative to solder a resistor.

Maybe J4bberw0ck can tell us more if i forgot something.I only apply the bridge mod to my first gsd 5 chip miner. There are for sure more jumpers and you can influence the output voltage in more ways but for me i think is better to stay with one mod at same time its possible to have unespected effects or that both methods add the voltage change and you have to much output.

For me this happens, at the same freq setting you have permanently change the chip voltage if you apply the resistor mod. Higher Voltage means more heat.


I don´t no any combination of both methods , but both results  in increase the chipvoltage to rise higher frequencies at very low Hardware errors. So if you have more Vcore and can set higher Frequency at very low HW this results in higher hash Rate. And have in mind that only the accepted shares counts for the effective hash rate.
There are for sure more "little" things to adjust this and get the best compromise between frequency and HW´s.
I don´t know if there are more benefits if you combine both methods for me more simple to replace just one resistor or to solder just one bridge.

The effective Hashrate for sure i think, if you have less Hw at the same Frequency , maybe the mining software say the same Hash rate for the same Freq but you get more accepted shares, if there was some HW´s in default mode.

Maybe the difference is not so big but if you set 925 Mhz @ 37.5 K the chips works with higher voltage than when you set 925 Mhz @ 36k. So the power consumption rise with the higher voltage and this produce more heat at the same freq.
So if you don´t want to overclock so much , its better to stay with 36K if this runs stable. Just an example : I have 2 blades , one with 36 K Mod ,one with 39 K mode, the one with 39 K Mode is a little bit faulty so i run them "only"  at 900 Mhz. The 36k one runs better so i set 950 Mhz , but even if the 39K one has a lower Freq it produce more or min. the same heat like the 36k one. That´s because this runs with higher voltage.

I hope this helps you a little bit , and maybe someone can complete or correct me if i´m wrong.Especially for the bridge mods you can read here more : ----> https://bitcointalksearch.org/topic/gridseed-5-chip-usb-miner-voltage-mod-519112

Gridseed Moddermen-

 I have been following this thread for the last couple of weeks.  It is really full of info, and it has raised some questions in my mind.

For starters, I have a Gridseed blade that was produced in Jun '14 (it has zero Ohm resistors).  From reading, I see one preparatory step, and three main mod steps:

          1) In preparation, improve the cooling with extra heatsinks.

          2) Replace the 33 KOhm resistor with another (36-to-44.2 KOhm examples given in the thread).

          3) Short 1 or 2 junctions for the "voltmod=1" configuration.

          4) Replace the 220uF, 16 volt capacitor can with a 220uF, 35 volt model with the same fit.

There are other improvements possible, such as changing the power socket, etc.

The questions I have follow:

          1) Are the modifications #2 and #3 above compatible?  I believe that J4bberw0ck put both in place.

          2) If both modifications #2 and #3 are performed, is more heat produced at the same hashing frequency?

          3) If both modifications #2 and #3 are performed, is a greater hash rate obtainable overall?

          4) If both modifications #2 and #3 are performed, is a greater hash rate obtained at a single frequency? 

It is my understanding that modification #4 does not directly improve the hash rate, but does improve the heat capacity of the blade at higher hashing frequencies, as the capacitor will stay intact longer.

One last question:

          5) If you use an adjustable pot and run at a set hashing frequency, say 925 MHZ, is the heat generated greater if the pot is set to 37.5 KOhm compared to the pot being set at 36 KOhm?

I hope that someone might take the time to answer.   Thanks for the difficult work already done!  -Scryptr

Damn I ordered the LQPF 48 (only on the 5 chip schematic) STM32 instead of the LQPF 64 for the blade, at least I also ordered samples from ST Micro of the 64 last week Hopefully it arrives asap

Don't you just love free samples ? 

Still waiting for the replacement STM32's, RS takes between 4-6 days to ship non stock items to South Africa.

I got the firmware from Gades, just hope it is for the 40 Chip Gridseed

Thanks for  your appreciation!
At the moment i try to do a study as an ingeneer in electronic communication. But i´m not so far and too lazy to learn.
I´m proud of me that i can participate in a forum in english that is not my native language. So sorry about any misspelling.
I only try to give something back to the forum , because i get some informations ,too.

And that´s the reason why only they can call themselves Mr. BIG.
No warranty, no money loss.
But what about the promise of fully decentralized crypto currencies?
Only if you have the real big money to buy at first the big Hash machines, you can get some profit.
So don´t care about warranties , try to do the best you can to maximize the income , so maybe don´t loose to much money.

Excellent explanation + table, Freeman2000yes ...

You seem to be pretty knowledgeable...what is your education / profession, buddy...

Thanks,

ZiG