A G-Technology head swap is mechanical work on the bare HGST or WD drive after extraction from the enclosure. Disassembly, donor matching, and reseal happen at the Austin lab on a 0.02 micron ULPA-filtered laminar-flow clean bench. We do not outsource head stack work. The same workflow applies to 2.5-inch G-DRIVE Mobile and ArmorATD internals and to 3.5-inch G-DRIVE desktop and G-RAID internals, with helium-specific steps added when the mechanism inside is helium-sealed.
Donor matching for WD-family heads
Heads inside G-Technology enclosures come from the HGST Ultrastar and WD Ultrastar product families. A donor that looks the same is not enough. Before any disassembly, we screen donor candidates against the attributes below so the donor head stack will read the patient platters, and which of them are decisive depends on the exact drive:
- Model family. Exact match on the HGST or WD model family (HUH721212ALN, HUH728080ALE, WUH721818ALE, and similar) including the platter generation suffix.
- Firmware revision. Donor firmware band must be compatible with the patient firmware band so SA tracks line up. Off-band firmware causes translator mismatch.
- Head map. Same head count and same physical head map. A patient drive with a disabled head must match a donor with the same active-head topology.
- Preamp ID. Preamp chip identifier and revision recorded in the SA. A swapped head stack with the wrong preamp will not negotiate read channel parameters.
- ROM adaptive zone count. Donor ROM adaptive zone count must match. WD-family drives store per-head adaptive parameters; mismatched zone counts make the translator reject the swapped stack.
- Manufacture date window. Donor manufacture date should fall inside a narrow window around the patient. Platter coatings and head fly height tolerances drift across production runs.
Donor inventory is indexed by those attributes. When a G-DRIVE arrives, the patient PCB is read with PC-3000 to extract the model, firmware, preamp ID, and ROM adaptive zone count before any donor candidate is opened. The procedure is documented further on our donor drive matching reference page.
Atmospheric purge and helium refill on helium-sealed G-Drive mechanisms
Breaking the seal on a helium-sealed Ultrastar mechanism inside a G-DRIVE or G-RAID enclosure vents the helium, so the gas has to go back before the platters turn again. The disassembly itself happens under our 0.02 micron ULPA-filtered clean bench in filtered ambient air, with the drive unpowered and nothing spinning, because the risk at that stage is particulate contamination rather than aerodynamics.
After the new head stack is installed, the lid gasket is replaced with a fresh seal and the chassis is closed. The chamber is then purged and refilled with high-purity helium through a calibrated manifold, and the drive is leak-checked at the seam before any spin-up. Helium refill on these units adds material and bench time to the recovery; that cost is published in our helium hard drive recovery pricing.
PC-3000 Portable III initialization and translator validation
A swapped head stack is not the end of the recovery. The drive comes out of the clean bench and onto PC-3000 Portable III for firmware initialization. We power the drive in safe mode, read the SA module to confirm donor preamp parameters were accepted, then walk the translator: rebuild or verify the LBA-to-CHS map, recheck adaptive zone tables against the ROM, and validate that each head in the new stack reads its assigned surface. Only after the translator is clean does imaging begin through the DeepSpar Disk Imager with retry counts tuned for the remaining weak heads.
This procedure is the same workflow we apply across all hard drive data recovery cases with mechanical damage. The G-Technology enclosure simply adds the bridge-board extraction step before the bare drive enters the head swap pipeline.