Also, SATA equivalent is M8_REV.07 100720903   . But you would still need to transfer that chip .

Also, when it broke, did your friend drop it or some other physical shock  ?  In the event heads got damaged or suffered sticktion to the platters, it may present more problems after the board part is solved.

Also, if you have the necessary equipment to cobble something together to read the flash chip , sometimes it is possible to read the chip from one board and reprogram the other without dessoldering them. Results may vary, depending on how the circuit of the board is implemented. Same as writing to BIOS flash chips on motherboards, where on some it is possible, and on others it fails.

thanks Silvio, great info. However, it turns out the replacement board is sold out and I have to start again. So: my search endet up at a canadian site where they offer free BIOS swap as part of the purchase price. (see links). So I will order this (and ship the broken PCB to them for the swap. Will report about this service when I get my parts in the mail. Only then can I see if there are other problems (such as shock) as you mentioned.

Oh, nice. It should work ok with minimum worry. Lets hope all ends well, and keep us posted.

Yes, the thing people are calling BIOS ( others call it ROM ). Whatever the name, it is a SPI flash chip that stores configuration parameters especific for that hard disk. Like a fingerprint of sorts. So, it needs to be swapped to the new board so that the disk can find the correct data. Sometimes, two disks/boards are similar enough that a board will work without chip swapping, but that depends a lot in your luck ( or lack of ) .

In the picture of your first link to the hddzone site, it would be the chip over the "Z" of their name.

Again, recomendable to take care when removing the chip because recreating the data in it is hard and costly.

One option, if you feel adventurous, just for the recovering of data, is to identify the traces and create a "bridge" with wire between the two pieces. Of course, that if the board is not muilti-layered in the broken part.

its cool to know a bridge might have worked. since the mission is to recover (my friends!) data, I took the easy route. but I'll try that next time if I get the chance. thanks for the tip!

hi silvio, tried the repair shop already. they ordered the wrong disk, and then gave up. so I will try. I am not sure at this point if there is an external BIOS to desolder.. So you say the BIOS is the 25U40 ?
 On the link (I posted) they have a set of instructions on how to swap the BIOS.. but it looks quite different to anything on my circuit board. At this point I am unsure which part I need to remove/replace.

(Delicate soldering is my speciality however, so I am confident to try this).

Your friend was really angry with the poor hard disk.

You need a board with the same code, then swap the chip marked 25U40 of yours  ( next to that bigger Marvell chip ) .

Those are very finicky to dessolder, though, and if you damage it, well, this data recovery will cost a lot more.

Taking it to a reputable data recovery shop shouldn´t cost much at this stage ( depends of which country/city you are on ), or you must be prepared to some very detailed soldering job, and also consult your friend if she is ok with risking her data, or if the data is important and she accepts to pay for a professional recovery job.