Donor heads fail when reading SA (Maxtor DiamondMax Plus 8)

[Serge_S]

Hello everyone,
I'm looking for an professional perspective on an old Maxtor Diamondmax Plus 8 (40 GB, NAR61590) HDD data recovery case.
Back in 2011, it stopped being recognized by the system (N40P in BIOS). At that time, some software diagnostics were attempted, but they didn't help. The drive was never opened. It was then put away on a shelf until late 2024. When powered-up, it intermittently showed up in BIOS as N40P and made clicking sounds. No DIY attempts were performed, it went straight to professional recovery lab.

- First lab reported the platters were fine, but the heads were bad. They tried two different donor heads without success. With no more donors available, the drive was returned.
- Second lab found micro-damage on the top platter surface (which is non-functional for this model). They also tried donor heads. However, when attempting to read the SA, the donor heads would fail. After unsuccessfull attempts they returned the drive with "magnetic layer degradation" verdict. Both labs use PC-3000 tools and have clean rooms. Unfortunately, no logs were kept.

What bothers me:
Both labs were confident during diagnostics that the data could be recovered. But as far as I know, both only swapped heads - no other steps were taken. I’m not a pro, but the fact that the drive's behavior (it spins, N40P shows up in BIOS) hasn't changed in 15 years makes me doubt that the problem is actually magnetic layer degradation. Also there's no visible platter damage. I hope that either the labs lacked the specific expertise for this ancient model, or they simply didn't have the motivation to dig deeper because spending too much time on one old drive just isn't cost-effective for them. Also an engineer from the one of the labs mentioned that with a large pool of donors, there might have been a theoretical chance.

This model is old and was known to be problematic back in the day, but when I've gone through most of the Maxtor-related threads on this forum, I haven't found a similar case, where heads fail during SA reading attempts. Based on forum threads, some engineers who were active in recovery during those years are very familiar with these N40P issues.
So please take a fresh look at this case. Is there still a chance for data recovery, or this "magnetic layer degradation" the only possible conclusion? I'm considering all options, including last resort measures. I would appreciate any thoughts. Also looking for a specialist who has the necessary expertise and sees potential in this recovery.
Thanks.

[pepe]

it is fairly pointless to speculate about this without actually evaluating the disk. It can be possible to recover data from that disk or partially recover it, but without checking and trying it is only grasping in the dark.

pepe

[Serge_S]

Thank you for your response, Pepe.
Please check PMs.