ST3500320AS SD15 Smooth Chip On Board Fried. Some questions

[joeybadoey]

Hi there,

My Seagate 500GB drive stopped working after a power surge the other day and when I opened it up I saw that the Smooth chip in the bottom right hand corner of the logic board got burnt. The little piece of foam was actually stuck to it. Of course now it doesn't even start up.

I have all my important files backed up, but I'd still like to try to recover the files on this drive.

I posted my story on the Seagate forum and was directed here.


I can get another one of these drives(I've seen them on ebay,etc), but I'm not sure if I'll be able to find the exact SD15 firmware.

So my questions are:
1. Can I get a logic board with a different firmware version and just transfer the EEPROM, or does it have to be the exact same SD15 firmware?
2. Where is the best guide to do this, and who would have the tools to do this job (sorry I looked quickly on the site, but couldn't find anything about this).

I'm not sure if I want to attempt this myself if it's very difficult.


Thank you,
Joey

[pcimage]

As long as the PCB p/n is the same and you transfer the EEPROM you will be OK (assuming no further damage such as preamp). The fw is stored on tha platters.

[joeybadoey]

Okay, before I purchase the drive I would like to test the preamp. Could you please explain where to touch the multimeter leads so that I can do this?

Also, so I need to match the P/N on the Seagate drive white label where it actually lists the S/N, model number, Firmware etc, or is that P/N found on the logic board or something? Sorry about this.


Thanks again,
Joey

[BlackST]

Multimeter ?!?

[joeybadoey]

Sorry, I was told on the Seagate forum that; "the SMOOTH motor controller also generates the negative supply (-5V or -4V ???) for the preamp inside the HDA. If the preamp is shorted, then your new board may also fail."

I was also told; "You can test for a shorted preamp by measuring the resistance between ground and the appropriate coil near the SMOOTH chip."

Where exactly do I place the leads to ground and which one is the appropriate coil?


I'm sorry, I don't know much about this kind of stuff. If the preamp is okay than I will purchase a drive and get a tech to do the transplant for me.


Thanks again,
Joey

[hddmania]

I think that is not a good idea if you really value your data and you want them back...

[zebong]

ohhh

you continue with the idea of transplant....

Why ?

[joeybadoey]

hmm, alright maybe I should have asked you guys what you recommend first!


So there was a power surge and the Smooth Chip is damaged.

What do you recommend I do now in order to get this hard drive working again?

[phishin_ca]

Joey, you are looking at a really inexpensive fix from a local guy. Why take a chance? Learning is one thing, losing is another.

[joeybadoey]

I'm really confused right now.

I was told on the Seagate forum and I have seen on many other sites that sometimes one of the diodes on the logic board gets fried due to a power surge.

Okay, so I unscrewed the logic board and found that the diode was fine, BUT the Smooth chip was definitely burnt.


So than I read about replacing the logic board with another exact one. Well you can't find the exact drive one with the exact firmware anymore, but you can find a similar one for $50 and just transfer the EEPROM.

OKAY, so I'll do that. I'm not going to do it myself, I'll take it to a tech for a reasonable price and they'll do it.


What's the problem? I see people do it all the time. I'm just going to throw it out anyways, and I'm definitely not spending thousands to fix it.


Anything wrong with that, let me know.

[phishin_ca]

<Podium>
Joey, absolutely nothing wrong with it. Actually it is commendable that you have the desire to learn the task. The problem is there are so many things that could be wrong with the drive to begin with, that there is a 90% chance that any suggestion will make it worse. The motor controller has a tendency to kill the preamp as well. You plug in the replacement, and wipe it out and now everyone here is the bad guy. Posts like the one that led you here are similar to the ones that have people connecting their HDD in the freezer to spinright. A proper diagnosis is the key and people here will will help as long as they are not attacked with the usual "I want to do it myself, and refuse to pay those outrageous fees". That being said I am 60% on the swap taking care of it for you, but for probably $50 more you could be sure </Podium>

[joeybadoey]

Okay thanks for the reply.

Well I have found the board on ebay. Exact firmware, etc. The only problem is that it's 16mb instead of 32mb.

I'm not sure if this matters at all?


The other thing is that I was told I could do a simple test with a multimeter to determine if the preamp near the smooth chip was destroyed. If that's so, I understand that buying another PCB or drive would be pointless. So if you could tell me where the preamp is on the board and where to connect the lead, than it will save me some money and time.


Thanks.

[hddmania]

A little bird is saying you might need something better than a multimeter...

[BlackST]

Joey, probably you are on the wrong forum....