Data Recovery Case File · Desktop Externals & Aging Drives · Assess Them Separately
One May Be a Component Repair and the Other May Not
His enquiry groups two drives under one explanation. A 3TB and a 4TB, both formatted for the same platform, which he believes "have suffered the same fate of wrong power." The event may well have been identical — and what it did to each of them will not be, because two drives of different capacities and generations carry different boards, different protection and different tolerances.
| Media | Two external hard drives of differing capacity and generation — both subjected to an incorrect supply; both non-functional; damage extent to be established individually |
| Reported situation | Two external drives of 3TB and 4TB · both formatted for the same platform · both believed subjected to an incorrect power supply · both non-functional · contents required from both |
| Fault class | Overvoltage damage of differing extent — protection components, regulation stages and tolerances varying by board design; mechanisms unaffected in both cases |
| Equipment used | Each drive assessed at component level independently · protection components checked as the first candidate on each · no power applied prior to board inspection · firmware memory transferred to matched donor boards where repair was not viable · each quoted separately |
The decode: why one event produces two outcomes
What an incorrect supply does: damages the entry stage — the protection components, the regulation that steps voltage down for the drive's electronics, and whatever sits immediately behind them. The damage is immediate and it is at the front of the board.
Why two drives will not have taken it identically: boards differ. A drive of a different capacity and generation has a different board design, different components and different protection arrangements — so the same excess voltage meets different circuits and fails at different points.
What that means in practice: one drive may have a sacrificial component that did its job, taking the fault and saving everything behind it. Replacing it restores that drive entirely, which is the cheapest outcome in this archive. The other may have had damage propagate further, requiring a donor board with the firmware memory transferred across.
Why they must not be quoted together: a single figure for two drives obscures the possibility that one is straightforward and one is not. He may want to proceed with one and decline the other, and a combined price removes that choice.
What is true of both, and it is the reassuring part: the mechanisms are untouched. A supply fault stops at the board — the motor never received the wrong voltage because the board failed before delivering anything, so no platter turned incorrectly and no head unparked. The contents of both drives are exactly as they were.
Why that makes this among the better categories of accident: the work is electrical rather than mechanical, does not require the assembly to be opened, and does not consume a donor drive.
What is worth establishing about the event itself: whether both were connected at the same moment or in succession. A supply that damaged one and was then used on the other is a different history from a single event affecting both, and it bears on whether the second drive was already compromised.
What must not happen: no power applied to either, correct or otherwise. A damaged regulation stage can pass the wrong voltage through to parts that survived, and that is how a repairable board becomes a replaced one.
On the bench
Each drive was assessed at component level independently — an identical supply event meeting different board designs, components and protection arrangements on drives of differing capacity and generation, and therefore failing at different points. Protection components were checked as the first candidate on each, many boards carrying sacrificial parts intended to fail first. No power was applied prior to board inspection, a damaged regulation stage being capable of passing incorrect voltage onward.
The outcome
Each drive assessed at component level independently, protection components checked first on both, and each quoted separately. Free assessment, one fixed written figure including VAT per drive, 50% of parts and labour upfront with the balance only on successful recovery. The decode: the event may have been identical and the damage will not be. Different capacities and generations carry different boards, so the same excess meets different circuits — one may be a single component and the other may need a donor board.
More than one drive damaged in the same incident
Have them assessed and quoted separately, and don't apply power to either — a damaged regulation stage can pass the wrong voltage through to components that survived. The event may have been identical but the damage won't be: drives of different capacities and generations carry different boards, different components and different protection, so the same excess fails at different points. One may have a sacrificial component that took the fault and saved everything behind it, which is the cheapest outcome there is. Separate quotations let you proceed with one and decline the other. And in both cases the mechanism is untouched.
Have both assessed separately — call Oxford Data Recovery on 01865 593000; each assessed at component level independently, protection components checked first, firmware transferred where a donor board is required.
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Our case files are drawn from genuine enquiries received by our laboratory over the past ten years, anonymised to protect client confidentiality. Each one describes the diagnostic and recovery procedure our engineers apply to that fault, using the equipment listed.