[Ed: A thread in which ztex is blamed for a faulty board]

[gusti]

Last October 21st I ordered 2 x ZTEX USB-FPGA Module 1.15x from manufacturer, through [Angry bastard mod redaction: Don't list non-public meatspace names] (owner of ZTEX).

Total price including overseas shipping was USD 929.-, I told [redacted] I was going to pay with bitcoins, as he told me he would be accepting them. Price with bitcoins was 10% more than with USD, I was not very happy with that , but I accepted the surplus to make transaction faster.

Ten days later, both cards arrived to my office, everything was correctly packed and seems alright. I asked [redacted] if there was anything special with choosing a power supply, he told me that not, that any consumer grade, supermarket, 5-12v voltage power supply was ok.

So I pulled a 12 VDC power supply from a working 3COM switch, checked the polarity, and connected one of the boards. Nothing came out, no led was on, and after connected to USB port, was not detected by operating system.

Suspecting a DOA on first board, I connected the second board, same result. After exchanging a couple of emails with [redacted], who blamed me before knowing anything about what really happened, I took both boards and sent them back to ZTEX for RMA.
Before that, out of curiosity, I measured the idle output of the PS with a digital multimeter : 13.5 VDC

Yesterday, that is only 40 days from initial buy order, Stefan received the cards, and he told that the voltage regulators were blown, and it was my fault for connecting the wrong power supply. And he was not planning to give me a solution nor a refund.

Blamed power supply is actually working with original 3COM switch.

I believe this is a plain SCAM, so , beware from buying anything from ZTEX.

tl, dr : Beware from buying anything from ZTEX, they will not honour any warranty.

[1714182500]

1714182500

[1714182500]

1714182500

[finway]

Hope Cisco will join the minertool industry.

[gusti]

Hope Cisco will join the minertool industry.

Cisco, pricey but rock solid. Never saw a router blow itself as this ZTEX FPGA board crap.

[JonHind]

I asked Stefan if there was anything special with choosing a power supply, he told me that not, that any consumer grade, supermarket, 5-12v voltage power supply was ok.

Before that, out of curiosity, I measured the idle output of the PS with a digital multimeter : 13.5 VDC

Why should this be covered under warranty? The warranty shouldn't have to cover a potentially faulty third party PSU.

[sadpandatech]

I know this wont make you feel any better, but those volt regs can be replaced.  In fact, if its the 8A Ezbuck one used on this board I have several hundred of them and would be happy to mail you 2.

  Cheers

[gusti]

I asked Stefan if there was anything special with choosing a power supply, he told me that not, that any consumer grade, supermarket, 5-12v voltage power supply was ok.

Before that, out of curiosity, I measured the idle output of the PS with a digital multimeter : 13.5 VDC

Why should this be covered under warranty? The warranty shouldn't have to cover a potentially faulty third party PSU.

What fault are you talking about ? Power supply is ok, and it's actually working with the original 3COM switch.

[gusti]

I know this wont make you feel any better, but those volt regs can be replaced.  In fact, if its the 8A Ezbuck one used on this board I have several hundred of them and would be happy to mail you 2.

  Cheers

Thanks for your offer, but I already RMA the boards.
I believe that ZTEX must do that replacing task, or refund me.

[chungenhung]

I asked Stefan if there was anything special with choosing a power supply, he told me that not, that any consumer grade, supermarket, 5-12v voltage power supply was ok.

Before that, out of curiosity, I measured the idle output of the PS with a digital multimeter : 13.5 VDC

Why should this be covered under warranty? The warranty shouldn't have to cover a potentially faulty third party PSU.

Wrong. If the guy told him any after market power supply would work, then that is not fault by the consumer.
If they want to prevent this from happening, they need to include the power supply.
Why do you think all the stuff we have come with a power supply of its own?

[Turbor]

So, you blow up two boards and then call someone a scam ? My board is working well at 12V. But we are talking here about "real" 12V from a power supply that cost at least as much as the "crappy" boards you purchased.   I'm almost sure that Stefan is going to replace the parts needed (at some cost as this was clearly your mistake imo). I had some initial problems with him that we had to work out but in my eyes that was something between me and him. A bit unfair that you come here and call him a scam. But that seems to be the way to handle things in the US.

[DeepBit]

Before that, out of curiosity, I measured the idle output of the PS with a digital multimeter : 13.5 VDC

Idle voltage may be not the same as with load. You should connect at least something like low-powered 12v lightbulb or some resistor.

[gusti]

So, you blow up two boards and then call someone a scam ? My board is working well at 12V. But we are talking here about "real" 12V from a power supply that cost at least as much as the "crappy" boards you purchased.   I'm almost sure that Stefan is going to replace the parts needed (at some cost as this was clearly your mistake imo). I had some initial problems with him that we had to work out but in my eyes that was something between me and him. A bit unfair that you come here and call him a scam. But that seems to be the way to handle things in the US.

Lucky guy you have your boards up and running, hope they never stopped running because warranty will not cover.
My both boards are blown, power supply is a 3COM one, actually working with a switch.

Talked to Stefan all day long before posting here, his final word is that he will not give any solution nor a refund.
If that not a scam, what a scam is ?

[gusti]

Before that, out of curiosity, I measured the idle output of the PS with a digital multimeter : 13.5 VDC

Idle voltage may be not the same as with load. You should connect at least something like low-powered 12v lightbulb or some resistor.

Sure, done that, voltage under load is 11.3 VDC

[Turbor]

Talked to Stefan all day long before posting here, his final word is that he will not give any solution nor a refund.

You mean free of charge or not at all ? You can talk about everything in a fair way for both. Now the ball is at Stefan. I hope he does the right thing and is replacing the defective parts.

[gusti]

Talked to Stefan all day long before posting here, his final word is that he will not give any solution nor a refund.

You mean free of charge or not at all ? You can talk about everything in a fair way for both. Now the ball is at Stefan. I hope he does the right thing and is replacing the defective parts.

I hoped that too, but his reply was that it was my only fault, and warranty does not apply.

[Turbor]

He has excellent ratings everywhere you look around, he invested much time in wikis + he seems to be a very intelligent person. He can not afford to fück you over !

I can understand you. I had this sh!t with a turbocharger i purchased in the states. It failed after less than 8000 km and no warranty was given... that sucks at a price of 2k dollars 

[gusti]

He has excellent ratings everywhere you look around, he invested much time in wikis + he seems to be a very intelligent person. He can not afford to fück you over !

I can understand you. I had this sh!t with a turbocharger i purchased in the states. It failed after less than 8000 km and no warranty was given... that sucks at a price of 2k dollars 

I also invested lot of money, shipping costs and time with these boards, taking the risk that they are a new product with not much testing.
And everybody knows that new designs may have problems. So I expected a fair solution proposal by ZTEX, which seems Stefan is not willing to give.

[Enigma81]

I just checked over the schematics of the 1.15x product that your'e talking about...

From my perspective (several decades of analog and digital circuit design, EE), there are two possibilities if in fact the power supply is 'blown up'.

The supply is capable of handling input voltages of up to 16V:
     references: http://www.aosmd.com/pdfs/datasheet/AOZ1025DI.pdf  AOZ1025 Datasheet (1.2v Supply)
                     http://www.aosmd.com/pdfs/datasheet/AOZ1021AI.pdf  AOZ1021 Datasheet (3.3v Supply)
                     http://www.ztex.de/downloads/usb-fpga-1.15x.pdf  1.15x schematic, where a note is actually included on page 4 near the power connector (Input Voltage: 4.5..16V)

So, even if your supply is putting out 13.X volts, it's not really capable of hurting the power supplies.  It's possible that he means "blew up the capacitors", but I really doubt a guy as smart as ztex would use caps not rated to AT LEAST 16, and probably 25 Volts on the input.

So, as said, I suspect two possibilities here:
1) There was a real and significant problem with the board, and the output of the supply or supplies was essentially shorted.  Assuming ANY level of quality control, pretty unlikely.
2) You plugged in a power supply that was putting out > 16V (knowingly, unknowingly, admitting or not admitting).

If no shorts or problems can be found with the board, and he told you using a 12V supply was safe (he can't assume that you mean a 12V supply that isn't a 12V supply, by the way, and 13.5 isn't 12...), I wouldn't warranty the board either.  Sorry, but I wouldn't...  Now, I would offer a reasonable price for repair and retest, but that's me..

I strongly believe that the board was fed significantly more than 12, 13.5 and even 16volts..  I've worked a LOT with smps parts (although not the AOZ102X in particular), and they can usually stand quite a bit more than their rating for a short period of time anyway... In fact, the absolute maximum of the AOZ parts from their datasheets is 18V, meaning they can survive that for at least some amount of time...

Unless their is something else to this story that I don't know - I really don't blame ztex for not warrantying the board for you.  Should ztex provide (or at least sell) a compatible power supply - yeah, probably a smart move.. but He told you to use 5-12, you admit you used 13.5, and it won't actually fail until 18ish.. Something isn't adding up here...

[likuidxd]

But that seems to be the way to handle things in the US.

[Turbor]

But that seems to be the way to handle things in the US.

Would you repair the boards after someone calls you a scam in every thread ?
Imo it was too early to complain here.

[DeepBit]

Talked to [redacted] all day long before posting here, his final word is that he will not give any solution nor a refund.
If that not a scam, what a scam is ?

May be he just forgot to include warranty part in the board price.

Actually it's a bit strange that both boards have such damage, not likely to be a coincidence, especially when other users have good experience with them.
So it's may be either you plugged in some other, not suitable power supply, or the boards are not working because of something not related to power and "blown regulators" is just a reason not to replace/fix the product.