Topic: bad Block Erupter? - page 2. (Read 8316 times)

I mentioned in an early post in this thread that the Block Erupter arrived and the small box had a seal that had been opened.  The box was unsealed.  I only own a single Block Erupter.  It's still not right.  I imagine it makes perfect sense to send returned bad B.E.s to customers who only get one.  No way to compare performance, is there BTCGuild.

^ was worse when I had something plugged into the Raspberry Pi hub next to the USB Eruptor. Ran ok for the few days. Now it's crapping out. Very hot to the touch but not sure how much. Have that basic included heatsink on the back but no fan. Don't want to put a fan on it really... noise...

Researching the crystal, there is a discussion about its "start-up" capacitor values tho it's an unrelated application.  The range of start-up caps was 18pf-33pf depending on which manufacturer's datasheet.  So, I made a small start-up network using 18pf caps and added it to the Block Erupter.

https://docs.google.com/file/d/0B_DLmNkCkkVpaE54VGd3dW50Wk0/edit?usp=sharing

There was no improvement with startup and possibly was more difficult to get running.  I see when the B.E. shuts down from ambient temperature >80°F, cgminer reports the hashrate goes into the gigahertz range.  I suspect the crystal but it could be a parasitic oscillation of some kind.  It remains to be seen if the added start-up network will improve functionality when ambient temperature rises above 80°F.

A replacement crystal arrived.  It has an upper packaging of the black material like an IC rather than metal.  I'd wonder about the metal, picking up heat from the CP2102.  The B.E. has been running well on a RPi but hasn't connected to bfgminer on the Vaio I use with zTex.  I first connected the BE to the USB2.0 hub is assess if the new crystal was soldered correctly.  The LED lit and flashed so yes.  There was a single failure to enumerate message.  The BE had no heatsink, top or bottom, but I had no intent of hashing yet.  I reassembled the heatsinks and tested again.  I now was getting clean USB connects to the Vaio, no error messages at all.  I changed the -S option on bfgminer from only the single port for the zTex to -S all, and tried both.  Bfgminer would hang.  I was seeing no indication bfgminer registered the presence of the BE.  

Putting the BE on RPi again, there was a single comm error and it was hashing.  Ambient is 73.4°F and excessive errors occur when ambient approaches 80°F so it should be fine.  It had accumulated 20 HW errors early but that has been unchanged for 25 of the 30+ minutes it's been hashing at ~334MH/s.

I tried the BE with the _USB3.0_ hub to the Vaio and quickly got a page of "unable to enumerate USB device" so changing the crystal isn't the solution.  I had determined the 11.xxxMHz was a crystal and not a resonator (which includes a pair of capacitors) by its size.  I'm using a 2010 Digikey catalog so maybe the 2012 show resonators in a 5mm x 3.2mm four pin package but this crystal behaves like the original so....  The resonators were larger.  Looking at the BFL Jalapeno schematics, they use an FT2232 and its datasheet shows it using a 6MHz resonator OR a 6MHz crystal with attendant external capacitors.  I don't see an appropriate capacitor pair for the BE 11.xxxMHz crystal.

So, it's leave it with the new crystal and put it back on the RPi.  

On another subject, I wonder if MinePeon startum+tcp can source to another system rather than run startum+tcp on two systems or if my best bet is to put the --no-stratum switch in cgminer.conf and use the same switch with bfgminer then run stratum-miner-proxy.

https://docs.google.com/file/d/0B_DLmNkCkkVpbWVWZkZvdlNFVzQ/edit?usp=sharing

https://docs.google.com/file/d/0B_DLmNkCkkVpLTducXJsVWwxSVk/edit?usp=sharing

Seems like a lot of buggering about.  I just point a 120mm across mine, and they work.  They get OMG hot without it and eventually crap out.  The 120mm fan is running off an old Netgear router PSU (12v).

The CP2012 on mine are cool to the touch, it's only the BE100 that's toasty.

Yes it is safe to run them for an extended length of time with out a fan. I have one that has run 24/7 for over 3 weeks.

Please do!  Would be cool just to see this image when hashing away.

If there is room in my usb hub, I'm going to stick small heatsinks on the Erupter's UART (CP2021), the regulator (AOZ1021) and the BE chip (BE100).

My intention is to extend the life of the device by bringing down the overall PCB temperature. The components that get hot may be ok with it, but the whole USB is getting very hot, and all the components will be cooking.

I have a small, quiet USB fan from ebay for $2 that will be running 24/7.

My neighbour has a FLIR camera, when I get my Erupters I will ask him for a picture or two and post them here.

I'll do before and after heatsinks.

Just wanna get my Erupters!

I just got a BE myself yesterday, all this talk about overheating as me wondering. Is it safe to run a BE without airflow over a extended amount of time? (over an hour) I'm wondering because this damned desk fan I bought(I'll replace it sooner or later I think) is pretty damned loud at night and was wondering if it's safe to it off during the night.

Maybe try this: shut down the fan, start it up so it fails to connect and gets hot.  Let it sit getting hot for some minutes.  Then when it's not going to get hotter, apply light pressure to the top of the CP2102 and shut down the power allowing it to cool while applying pressure.

If the hottest part of the CP2102 is at the internal bottom facing the ground plane and if it's suppose to be soldered but wasn't heated enough, since the temperature above the CP2102 can reach 250°F+, then the area near the ground plane is hotter, perhaps hot enough to liquify the solder.  If so, after cooling and having pressure applied topside while cooling, the next time it fires up the ground plane can draw away the CP2102 heat more effectively.

That or the BE gets killed.

Oil Cooling?

What's your ambient?

You might try a heatsink designed for a TO-220 transistor.  That's what worked well to cool the CP2012 while under a fan - I needed to modify a Teflon washer of the kind typically found in a TO-3 transistor mounting kit.  It's fairly large so I had to cut a 90° notch so it would fit then had to lap it sandpaper to get the  height right.  Then you need to get a #3x.50-10 screw to hold it in place and a dab of heatsink compound.  It doesn't sit square and in fact is 45° off the line so it doesn't see interference from the USB connector.

I wonder if the CP2012 needs to be soldered to the board at its center so it could cool better but I'm not going to expose it to high enough heat to test the theory.  I suspect the problem is more closely related to the 11.xxxx crystal.  Note there is very little information on the crystal aside from the frequency.  The BE manufacturer may have gone to cheaper crystals that can't take much heat.

I have a bad block erupter also bought from btcguild. It works if its cool for maybe a minute but doesn't work at operating temp. Have a 120mm fan on it and it averages about 140mhash after all the hardware errors

Right, the 11.xxxxMHz crystal. 

Wonder if a simple barrier of some kind between the CP2102 and the crystal would improve communication.  Not metal naturally, a thin piece of Styrofoam as a wall sitting on double sided tape would show if the approach would help.

I'm sorry, i meant the oscilator. i miss quoted. there are two, one for the system and one for the ASIC?(i think). i was wondering which was giving you problems. since people have speculated about over clocking these miners, i was thinking it would be convient if you were playing with the right one, although i suspect that you aren't.

The CP2102 datasheet indicates the chip is a USB2.0, interface I believe.

It's the cgminer indication of the BE stats I believe:

AMU 1: | 333.3M/334.9Mh/s | DA:392 DR:1 HW:2 WU: 4.45/m

I am fairly sure that the Block erupter is a USB 1.1 device, I read that somewhere.

You know that Raspberry Pi doesnt work with USB 3.0 hubs?

Your work with your faulty BE is very interesting.  I had already decided to put a small heat sink
 
http://www.ebay.com.au/itm/120970427830?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649

on my BE chip, but I'm going to put one on the CP2102 now as well.

Still waiting for my 4 BE's, and a longer wait for my early June 2013 Jalapeno order

Phil

Is that the system timer or the hashing timer?

The room temp dropped to below 80°F, the B.E. had been disconnected from cgminer and the miner sitting idle.  I flipped the BE upside down so the attached fan would be drawing air from below thru the steel bars of the rack, unplugged and hotplugged the BE, it came up and has been hashing okay.  I think the 80°F temp is the key.  Still, the failure to connect to anything but the RPi is unacceptable.  I've ordered two crystals, one good for 85°C at the correct frequency and one good for 125°C at 12.000MHz.  What the heck right?

 AMU 1: | 335.1M/334.6Mh/s | DA:165 DR:0 HW:2 WU: 4.71/m