Ninjastic
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Board Mining (Altcoins)
Re: GRIDSEED G-BLADE Overclocking 7Mh/s
by
Freeman2000yes
on 14/07/2014, 20:41:42 UTC
Hi,

I have some news, too.
My ordered parts arrived now and i replaced them so far.

This is what i replaced :





And don´t be afraid to order from Mouser , if you are not in the USA . I was also a little bit afraid , after i had some bad experiece with my orders from USA to Germany,
but in this case it was really a dream! Just 2 days to arrive , no extra costs for customs or other fees. Even if i order directly in Germany this would not be faster, and in other shops it is really difficult to find the parts.

Some conclusions (for beginners)  Wink:

  • The upper Mosfet (this was absolutly the reason why the power source shut down - Thanks to Styson and Barssguy) was really hard to desolder with hot air , i have to remove the Cooler from the PCB and it takes a lot of time. Surprisely it was also hard to solder the new
    one , it fits perfect to the older size , but i was afraid to do this with hot air , not to damaged it , and i have to use a lot of flux but it was really difficult to apply it. i made it finally , not perfect but it works so far. Mybe to use soldering Paste which has a lower melt point isn´t a bad idea
  • Be very carfull not to scratch the PCB , when working with sharp tools, especially when the protecting surface is hot.
  • The Ame8805 was easy to solder , but everytime you have to clean with isoprpyl before apply and fix it with tweezers. You also have to be very carefully with the heat not to apply to long , some seconds more than expected over 300 C and you destroy it. And have in mind that this parts are very moisture-sensitive. in the bag is an indicator , if this is not blue you have to bake them. And also not apply to much solder !
  • For the AFB26 ( maybe this just a liitle bit melted part cause the fault to the AME8805 - thanks to J4bberwock) just remove the older one carfully not to damage the tracks under , in my case the tracks was not damaged from melting. And a 0- OHM Resistor ( i take the one with high power) works definitley. For a long time period i don´t know but i think it looks good at the moment.
    For those ones who has more real FB on the Board , replace them with 0 Ohm.It´s more secure , than to have the posibility to damage the PCB.My PCB was originaly send form Hong Kong and I have only 0- OHm Resistors in the Place for the FB´s directly form the Factory , just the AFB26 was a real FB.
  • The Capacitor was harder to desolder than i thought , with hot air , may the plastic part begin to melt , and again be carefull not to pull them to much.
    I don´t know if the one i choose ( 220uf 35 V ) is really the best choice , may some one has a better alternative?.
  • And don´t forget , it´s highly recomended to have some basic things like desoldering wire/stripe , a hot air station, and a Flux Pencil. Also try to remove the old solder that remain on the pads and apply new one which is recomended for SMD.It´s better than to damage more. This was my mistake too , so i thought : "Let´s start to solder SMD without any tools , just a soldering Iron." ---> Bad idea. After some impressions i highly recomend , if you are not a proffesional , to think twice , the things are not so easy than they appeard and just one wrong move and your investment is gone... the current prices for Scryptmining are sad enough , so don´t make them sadder.If you have a little bit experience in this things , so my recomend is not to hesitate and prepare everything calm, just a few days without mining are not so expensive like a valueless device. Also don´t forget to apply coolers on any important part, like Mosfets , Choke R , and backside of the PCB , I also apply a small cooler on the Capacitor which was original the 16V one and only to be absolutley sure one small cooler on the AME8805 from USB side.But the most important thing :  USE A FAN to cool the powersource part backwards! Just to show how important this is : my powerplugs ,i don´t apply screw terminal ones , are purley melted and destroyed under "normal" overclocked conditions with 39Kohm and 938 Mhz!!!!, just even if i used good copper stripes 2.5mm, so to replace this with screw terminals are much more better.Keep in mind that only with the front Fan , the airflow decrease significantly backwards , and it has allready accumulate all the heat from the cooler part , so you try to "cool" with "hot" air. This was not a big invention from Gridseed, under summer temperature , you may have heat problems und normal conditions , without any overclock. They try to compensate this with the more powerfull Fan in the front, but this is a loud and inefficient sollution. I use now 2 Arctic Fans with Temp Sensor, one in the front and the other one i mount backwards with screws on the original cooler, so the hot air from the front fan AND the power -part , is blowing away to the side.And if you apply the fan on the side , the Blades are able to place one above the other.



So i hope this time it works better and longer , after replacing the AME and the AFB26 the USB Communication works again.
If it works i hope that the price drop don´t continue like this , that i don´t have to use my 2 G Blades only for heating my home in the winter.

And thanks to all the guys ,who spend they time to made this thread.

Has anyone an idea how to opperate with cgminer 3.72 and win xp and not tho have to unplug the Blades form USB and Power when I change them Pool or freq?
I try the newest BFG Miner it has not this fault , but it don´t works so fine like CGMiner, after some times the stratum is interrupted.