I removed two 8GB DDR4 memory modules from a broken iMac and would like to reuse them in a desktop PC built around an Intel Core i7-8700. I also want to install a dedicated graphics card. The iMac modules are laptop-sized, so I'm trying to find out whether a compatible motherboard exists or whether an adapter can let me use this SO-DIMM memory in a standard desktop system.
3 Answers
The i7-8700 uses an LGA1151 socket and a 300-series chipset, so look for a motherboard designed for 8th-generation Intel processors, such as a B360, H370, Z370, or Z390 model. Most of those boards use full-size desktop UDIMMs, not laptop SO-DIMMs. A SO-DIMM-to-DIMM adapter can sometimes work, but it is not guaranteed and the memory may need to run at conservative settings.
First, confirm the exact RAM type. iMacs commonly use SO-DIMM modules, but the generation matters: older models may have DDR3, while the i7-8700 requires DDR4. If the modules are DDR4 SO-DIMMs, they may work with a suitable adapter, but the motherboard still needs to support DDR4 and the adapter has to be compatible with the board and memory.
The modules are 8GB DDR4 sticks, so the memory generation should match the i7-8700. I’m mainly unsure whether the adapter route is reliable.
Check the iMac modules for their label and confirm they are unbuffered, non-ECC DDR4 SO-DIMMs. If they are the right voltage and specifications, an adapter may let you test them, but buying a used motherboard with normal DDR4 desktop slots and a matching memory kit is usually the safer and less troublesome option. Also verify that the iMac RAM is actually removable rather than soldered.
Make sure the board specifically supports 8th-generation processors; older LGA1151 boards generally cannot run an i7-8700 even if the socket looks identical.