Soldered RAM makes MemTest86 trickier but not impossible.

It still works. MemTest86 doesn’t care if the RAM is soldered or in a slot. It tests the memory chips, not the connection type.

The real issue is what happens when you find errors. With soldered RAM, you can’t just swap the bad stick. If MemTest86 reports failures, you’re looking at a whole motherboard replacement (or a new machine). That’s not a diagnostic limitation, it’s a repair limitation.

There is one practical catch: some laptops with soldered RAM (especially thin ones) might not boot from USB reliably for MemTest86. That’s a BIOS/UEFI issue, not a RAM issue. If that happens, you can try a different boot medium or use the Windows Memory Diagnostic tool from within the OS.

But the test itself? It works the same. Soldered RAM doesn’t hide errors from MemTest86. So go ahead and run it. Just be prepared for an answer you may not like.