12 RTX 3070 GPUs Found Abandoned in a Basement

A user identified by the handle CelebrationIll9568 on Reddit’s r/pcmasterrace forum obtained two complete, decommissioned mining rigs free of charge after asking a previous owner who had left them unused in a basement.

The machines contain 12 Zotac-branded Nvidia GeForce RTX 3070 graphics processing units (GPUs), along with two MSI MPG Z390 Gaming Plus motherboards, two 4GB DDR4 memory modules, two 120GB solid-state drives (SSDs), and multiple power supplies. The collection includes a 1000-watt Gold-rated unit manufactured by Rosewill.

The central processing units (CPUs) were not explicitly identified. A stock Intel cooling fan is visible, confirming an Intel platform configuration, while MSI’s Z390 motherboard line uses Intel’s LGA 1151 socket for 8th and 9th Generation Intel Core processors based on the Coffee Lake microarchitecture.

Nvidia launched the GeForce RTX 3070 in October 2020 with a manufacturer’s suggested retail price (MSRP) of $499. Built on the 8-nanometer Ampere architecture and fitted with 8GB of GDDR6 video memory, it became one of the most sought-after GPUs for gaming and cryptocurrency mining. During the 2020–2022 supply shortages, individual cards frequently sold for more than $1,000.

The equipment dates to the peak of the pandemic-era Ethereum mining craze, when standard consumer graphics cards ran around the clock to calculate cryptographic hashes in exchange for digital tokens. Motherboards with multiple PCI Express slots were routinely sought during the mining expansion because they could host several graphics cards through PCIe riser cables.

The recipient said they primarily operate within the Apple Mac ecosystem and had no previous PC assembly experience. They turned to online technical forums to assess the physical condition of the components.

The broader 2020–2022 crypto boom created vast quantities of specialized computer hardware. Years after energy costs and network upgrades made small-scale domestic mining unprofitable, substantial caches of high-end equipment continue to be found in residential storage spaces.

Ethereum mining changed permanently on September 15, 2022, when the network completed “The Merge.” The blockchain moved from a Proof-of-Work (PoW) consensus mechanism, which depended on hardware computational power, to a Proof-of-Stake (PoS) system. Electricity consumption fell by an estimated 99.95%, and GPU-based Ethereum mining became obsolete.

Alternative PoW digital currencies did not offer enough profit to cover residential electricity tariffs, leading to widespread decommissioning of domestic mining rigs across North America. On current secondary markets, functioning RTX 3070 cards sell for between $350 and $450, depending on condition and brand variant. Assuming all 12 recovered Zotac graphics cards remain fully functional, their combined market value is between $4,200 and $5,000.

Several GPUs show visible liquid residue on their printed circuit boards (PCBs), raising the primary technical concern during the inspection. Hardware maintenance commonly refers to this condition as “silicone bleeding” or thermal pad sweating. It occurs when the silicone oil binder in thermal interface pads separates after prolonged exposure to elevated temperatures, such as those produced by 24/7 mining operations.

Although the residue can look alarming, silicone oil is chemically inert and non-conductive. It generally does not short-circuit electronic components or permanently damage the underlying PCB. Experienced hardware technicians advise that affected cards can typically be restored by disassembling the GPU shroud, cleaning the residual oil with high-purity isopropyl alcohol, typically at 90% concentration or higher, replacing degraded thermal pads, and applying fresh thermal interface material (thermal paste) to the graphics processing die before reinstalling the units in standard desktop configurations.