Quote from: gbyg on May 18, 2014, 09:30:28 PM

Quote from: nst6563 on May 18, 2014, 08:47:35 PM

Wow...no pinched fan cables or anything? How long has that one been mining up until that happened? What type of power supply were you using? What's the ambient temp where it's mining?

Sorry for the questions, but I've got 6 that have the 49.9k/50k mod. 3 have been running non-stop 24x7 for 2 months, the other 3 have been running non-stop for about 3 weeks now. When I've modded them, I did add some small heatsinks to the mosfets because a little extra cooling never hurts when overclocking anything.

I suppose repeated high current spikes and overheat may help damage the mosfet, I think those little LFPAK rated for 76AMP might be possible but to allow continues drain @76AMP the pad need to be able to handle the heat dissipation of SMD mosfets. Which explain why they are overheated and blow. For same reason anything to cool this baby down will help bigtime!!

X-cuse me yooze guys,..

You're talkin about our little 5 chip seeds, right? How the F**k can they be blowing up FB's and FET's and Hash chips like that?
I'm just amazed at how many seeds are taking a dump for no good reason.
Have any of you attempted mods different than those specified where known proper and workable alterations go? You know, the ones where the top heat sink is left on with fan running at either full or a bit less than half speed?

My guesses are: inadequate cooling via alterations that have backfired under normal Scrypt overclocking.
The entire card is meant to be FAN FORCE COOLED even though they are not directly sandwich style heat sinked the same way the main hash chips are. I know this for a fact because I recently took apart and dusted off 6 of them as part of converting 5V USB to 5V regulated via 12V source after months of 24/7 cooling at 5V fan speed.

Perhaps it was a batch of bad FET's and or Hash chips or even FB's...It HAPPENS! And it is quite possible we are witnessing one of those coincidences right here on our forum. More than one person in the group got stuck with a faulty seed or seeds from one of those bad batches. There are always a small % of DOA's in most batches, I am sure.

Some yet discovered mistake being made during any of the VMOD's?

Reasons for my amazement:
Scrypt should not cause an over-strain on any components! Period!
After all, they are made to run SHA-256 at 60+W, for Aunt Jamima's sake!
Scrypt at full blast won't even touch that figure if even by half! NEVER! Or something is very wrong with the components.

I've had 6 overclocked seeds running for months now virtually 24/7 with no adverse hardware issues or firmware issues, whatsoever! Just like it should be. I also have 20 more that have been running faithfully for weeks same same.

Worrying about using more powerful FET's is a waste of time for if you have to, then there is something wrong with your seed/s! Something else on there is backing up current flow where it shoudn't be and causing failures. They are defective! So you're either stuck with a patched up overheating POS now or shyt can them and buy some new ones. Maybe you can swing a discount, that is - if you can get your supplier to feel sorry for you Wink