Repair technician "northwestrepair" on YouTube reveals the dangers of using copper memory cooling mods on GPUs. In a RTX 3080 repair video, the technician shows the damage done by a user who modded his founder's edition RTX 3080 with a copper mod. Extensive damage to the GPU's 1.8V rail, memory voltage, and other sub-systems was evident.
Copper modding, in this context, is a cooling upgrade for graphics card VRAM that can significantly improve memory temperatures. The mod involves replacing the stock memory thermal pads with a copper cooling plate (or copper shims) that sit between the memory ICs and the GPU heatsink. Thermal paste is then used to bridge the small remaining gaps.
While this mod can massively improve temperatures, northwestrepair reveals that copper mods can impose significant danger to the system components surrounding the GPU. Any component near the memory ICs is vulnerable to damage, as a result of copper's electrically conductive properties.
That is exactly what happened to the RTX 3080 northwestrepair fixed. Despite the original owner's attempts to protect the surrounding VRMs with Kapton tape, the GPU suffered immense damage making the GPU completely unusable.
The repair technician discovered a variety of issues with the GPU including a short in the memory power delivery system, and several knocked-out capacitors and components affecting the 1.8V rail, 5V VCC, and other systems. Other damage was also discovered including cuts to some of the traces near the PCIe finger, as a result of bad handling of the card which the technician also had to repair.
However, the most problematic issues were related to the GPU die and some of the memory ICs. The technician suspected thermal paste might have made its way underneath the GPU core and/or memory ICs. After reballing (reinstalling) and cleaning the GPU core and two memory ICs that failed memory testing, the card finally posted and passed a FurMark stress test. Confirming that thermal paste or some foreign debris was interfering with the memory and/or GPU core.
Northwestrepair noted that memory temperatures during the FurMark stress test were perfectly acceptable (after he swapped out the wrong pads with the right-sized counterparts), with the GDDR6X memory temps hovering in the high 70s negating any need for modding the cooler.
Copper shim and copper plate modding gained popularity a few years ago, when GDDR6X first debuted on the RTX 30 series and when crypto mining was still profitable on GPUs. These two factors created a massive overheating problem on many RTX 30 series GPUs, with several GPU models running upwards of 110C on the memory, while mining causing thermal throttling. This problem was especially troublesome on the RTX 3090 (not the 3090 Ti), with half of its 12 GDDR6X modules being on the back of the PCB, RTX 3080 Ti Founders Edition, and RTX 3080 Founders Edition.
Using copper mods drastically helped reduce temperatures on these problematic cards ranging from a 25C to a whopping 46C reduction in VRAM temps depending on the copper mod implementation and card model. However, it was only truly beneficial on mining cards, as games rarely caused these GPUs to thermal throttle.
