GRIDSEED G-BLADE Overclocking 7Mh/s, improvements and repair - page 15.

styson

newbie

Activity: 20

Merit: 0

Quote from: Blisk on June 03, 2014, 03:13:32 AM

Did anyone meassure ferrites which needs to be replaced?
Have anyone data?

Impedance:?
DC Resistance Max:?
DC Current Rating:?

The 1206 size Ferrites are 300 Ohm 100Mhz 3A, the 0805's are 300 Ohm 100Mhz 1.5A

You can just use 0 Ohm resistors in their place or bridge it with 2-3mm thick of solder.

I replaced mine with 120 Ohm instead of the 300 Ohm and no problems.

Blisk

sr. member

Activity: 412

Merit: 250

Did anyone meassure ferrites which needs to be replaced?
Have anyone data?

Impedance:?
DC Resistance Max:?
DC Current Rating:?

styson

newbie

Activity: 20

Merit: 0

After putting in the CSD16321Q5C the stock 220uf gets very hot, just a warning to others, you might want to put a 20v or 35v cap in its place.

powersup

sr. member

Activity: 406

Merit: 250

I just wanted to say what a great job you are all doing. I have recently received a blade and plan to volt mod.

I do have a couple of questions which i hope someone can answer.

1. Can I simply bridge across FB23,24,25,27,28, and 29 and leave the ferrite beads in place?

2. what would be the max resistor value you would recommend if I don't replace the 220uF/16V cap, but instead add a heat-sink and actively cool it.

Thanks in advance.

Blisk

sr. member

Activity: 412

Merit: 250

you won't get that much more out of blade when water cooling. You will use much more electricity

styson

newbie

Activity: 20

Merit: 0

Quote from: styson on May 28, 2014, 01:41:04 AM

Quote from: J4bberwock on May 26, 2014, 08:34:39 AM

Quote from: styson on May 26, 2014, 05:22:44 AM

Lost them while busy trying to find a short on the board, 3 Ferrites were blown and the FET is shorted !!! Waiting for replacement FET's now.

Thanks J4bberwock

anything else than the ferrites and fet blown?

it can be helpful for some other people.

As far as I can see, nothing else damaged, I did get a confirmation from gridseed that you can use 100ohm 1206 100Mhz Ferrite Bead instead of the 300ohm 1206 100Mhz bye the power plug, but they say you can't go lower than that, but I suppose if your using a good quality power supply you can just put a 0ohm resistor in the or jumper it like you guys do.

As for the FETs, I have ordered :

CSD16321Q5C (replaces IRFH5302) * Dual Cool
CSD17556Q5B (replaces IRFH5300) * Correction these are not DualCool

Which are the DualCool type, should run a lot cooler Grin

Sorry guys, just made a correction on the above post, the CSD17556 is not DualCool.

Got the CSD16321Q5C on 1 blade so far, much cooler, finger does not burn now when I touch it Cheesy

Will Change the CSD17556Q5B's this week and then to do the resistor mod.

If I increase the resistor by say 3K, what will the heat be like on the gc3355's are heatsinks needed ?

Wish I had my cnc milling machine up an running, would have converted the whole blade to water cooling.

Blisk

sr. member

Activity: 412

Merit: 250

It is more problem to get chips off than on.
When you solder you need a sharp point on and using magnifier, it is hard to do, but with some experiences it is not that hard.
If you never did that than it is not for you.

DarkKnight

full member

Activity: 178

Merit: 100

You still need to reattach them with something. You can't solder the pad underneath with a pencil, I think. I was looking at my blade today, and that damned resistor is so tiny.

The last SMD IC I tried to replace (not mining related) was a damned disaster. I ended up using a razor blade to carve the solder out between the pins because they kept bridging.

I was thinking about the power jack problem, 8 pin EPS connectors are (unoffically) rated to >300w. An extension cable would provide the connectors needed, and one would only need to cut it in half and creatively solder the pig tail to the board properly. I don't suppose it would be pretty, but GC should really have equipped the board with it in the first place. That should comfortably supply 12.5A to each blade. PCIe would also work, but should really connected observing the ATX spec (3 +12v, 5 GND), in case someone actually plugs a PCIe cable into it to power it, and that's rated to 150w. Using either would stop the melting power connectors, I suspect.

Blisk

sr. member

Activity: 412

Merit: 250

I will just cut off the mosfets it is much easier and than throw it away.

natbyte

member

Activity: 70

Merit: 10

You can use a normal iron, for the capacitor and resistor changes, I just used a fine tipped 40 watt soldering iron, however for changing a mosfet you will need a hot air setup.

DarkKnight

full member

Activity: 178

Merit: 100

It's not entirely clear what you are asking, but it sounds like you didn't read through the thread. Roll Eyes

You want to O/C your blade? Stop skimming and read through the entire thread. I've read all 17 pages many times, you can do it at least once.

Those of you doing mods, are you using rework stations or a pencil iron?

kaltar

sr. member

Activity: 805

Merit: 250

Quote from: DarkKnight on May 30, 2014, 11:06:06 AM

Quote from: kaltar on May 30, 2014, 09:26:14 AM

Small question, i have a bunch of 49.9k ~~vertical~~ axial resistors from moddings seeds, can i use one to mod a g-blade and just keeps an eye on tempeture and not go above lets say 1000mhz .?

Only if you want to fry your power MOSFETs in short order. It's not the set speed that damages the components, it's the current your trying to push through them. AFAIK, 43k is the highest anyone has gone, and that creates enough heat to melt the power jack.

So many people just soldering crap on and off, not even really understanding what they are doing, or the consequences of it. Makes me wish there was a root privilege lock out for hardware.

ok, so no more than a 39k but i can still use an axiel one. ? and is there a side to hit. ?

DarkKnight

full member

Activity: 178

Merit: 100

Quote from: kaltar on May 30, 2014, 09:26:14 AM

Small question, i have a bunch of 49.9k ~~vertical~~ axial resistors from moddings seeds, can i use one to mod a g-blade and just keeps an eye on tempeture and not go above lets say 1000mhz .?

Only if you want to fry your power MOSFETs in short order. It's not the set speed that damages the components, it's the current your trying to push through them. AFAIK, 43k is the highest anyone has gone, and that creates enough heat to melt the power jack.

So many people just soldering crap on and off, not even really understanding what they are doing, or the consequences of it. Makes me wish there was a root privilege lock out for hardware.

kaltar

sr. member

Activity: 805

Merit: 250

Small question, i have a bunch of 49.9k vertical resistors from moddings seeds, can i use one to mod a g-blade and just keeps an eye on tempeture and not go above lets say 1000mhz .?
and if yes, wich directions (side ) do i solder the top of the resistor ( yellow line ) or its doesn`t matter.

thanks

styson

newbie

Activity: 20

Merit: 0

My CSD16321Q5C arrives today, gonna solder them tonight and have my second blade up and running Grin

CSD17556Q5C arrive next week only, so will try them then.

GenTarkin

legendary

Activity: 2450

Merit: 1002

Quote from: wolfey2014 on May 28, 2014, 02:00:42 PM

Quote from: GenTarkin on May 28, 2014, 12:35:06 PM

too high? anything 2% and lower is a gain....
Also, naw, the wire mod allowed me to go from 913 to 925 at same or less HW%

What?
Okay, have it your way Wink

That is .25% ... vardiff calculated =)

So the calculation is (HW * vardiff) / (Diff1A + Diff1R) * 100

wolfey2014

sr. member

Activity: 378

Merit: 250

Quote from: GenTarkin on May 28, 2014, 12:35:06 PM

too high? anything 2% and lower is a gain....
Also, naw, the wire mod allowed me to go from 913 to 925 at same or less HW%

What?
Okay, have it your way Wink

GenTarkin

legendary

Activity: 2450

Merit: 1002

too high? anything 2% and lower is a gain....
Also, naw, the wire mod allowed me to go from 913 to 925 at same or less HW%

wolfey2014

sr. member

Activity: 378

Merit: 250

Quote from: ZiG on May 28, 2014, 12:00:17 PM

Quote from: GenTarkin on May 28, 2014, 09:47:40 AM

Quote from: Blisk on May 28, 2014, 01:32:59 AM

Ok but you must be avare of making extra inductance on the board after that.

I barely know anything bout electronics, I just know this type of mod has been attempted on several multi chip ASIC designs in the past. So, wanted to try it on gblade.
Its helped a bit, just not as much as Id hoped =)
So, all in all, w/ the wire mod & bridge mod, Im at 925mhz .25% HW avg across all my blades.

Good job, buddy...

Bridge mod = VMOD1...Correct...?

ZiG

I would un-do that mod if I were you....you're probably going to lose more than you gain in the long run with that particular mod..... .also .25% HW error is too high...

GenTarkin

legendary

Activity: 2450

Merit: 1002

Quote from: ZiG on May 28, 2014, 12:00:17 PM

Quote from: GenTarkin on May 28, 2014, 09:47:40 AM

Quote from: Blisk on May 28, 2014, 01:32:59 AM

Ok but you must be avare of making extra inductance on the board after that.

I barely know anything bout electronics, I just know this type of mod has been attempted on several multi chip ASIC designs in the past. So, wanted to try it on gblade.
Its helped a bit, just not as much as Id hoped =)
So, all in all, w/ the wire mod & bridge mod, Im at 925mhz .25% HW avg across all my blades.

Good job, buddy...

Bridge mod = VMOD1...Correct...?

ZiG

Yeahp, I think =P ... lol, its the one where u close to 2 x 2 solder pads and it brings it up .1v

Topic: GRIDSEED G-BLADE Overclocking 7Mh/s, improvements and repair - page 15. (Read 74130 times)