How to find a donor PCB for HDD data recovery.
In a follow up to the initial post, “How easy is it to find a donor hard disk drive? Part 1”, this section explores the issues associated with finding donor parts for faults associated with a printed circuit board (PCB) on a hard disk drive. Faults with a PCB are one of the most obvious to the end user – the hard disk will not spin up, and there can often be visible damage to the components on the PCB and the smell of burnt solder. These typically happen after a power surge, or an incorrect power source being connected to the hard disk drive.
Given how obvious the fault can be many users assume that recovery of the fault will be equally as obvious – find a PCB, put it on the HDD and “hey presto” a working HDD. Sadly on nearly all modern HDDs this is not the case, as most PCBs have unique data on them. This unique data (adaptive data) needs to match content in the firmware which is based on the platter surface. This means that when we find a suitable we need to remove component from the failed patient PCB or recreate the content using data found in the firmware service area.
Western Digital HDDs can be particularly challenging to find donor parts for. The reason for this is the frequent revision changes on critical parameters. The example below denotes just some of the requirements when considering to work on this hard disk drive. There is another, which is not listed on the HDD itself. This relates to the ROM / ATA module. There is no way of knowing this just by looking at the drive. As you can imagine this can be very frustrating! Consequently it is wise to keep a large stock of donor drives, which we do.
For all those trying to find donor parts a mention must go to Access Computer Parts / Fred Farzan based in California. Everyone that has worked in the data recovery industry will be familiar with Mr. Farzan. If there’s a rare hard disk drive you need that you can’t find any where else, he’ll have it.