I have an 8–9-year-old Acer Nitro 5 AN515-51-766E with two memory slots. It originally had 16GB of RAM in a 2×8GB configuration, and I replaced it with 32GB using two 16GB modules. The laptop's CPU supports DDR4-2400, while the new modules are rated for DDR4-3200, so I'm wondering whether the speed difference is causing the problem.
With the new RAM installed, the fans start briefly and then stop, and the laptop does not show anything on my external monitor. The BIOS also appears to shut off the monitor. The laptop's built-in screen has been unusable for years because of broken hinges, so I rely on an external monitor connected over HDMI.
I tried disconnecting the CMOS battery and reinstalling the RAM several times. The modules appear to be seated correctly, and the original 2×8GB kit still works, so the slots and pins seem fine. The laptop seems to boot with the new memory, but I get no display output. Could the 3200MHz modules be incompatible, or is there another likely cause?
2 Answers
Try testing one 16GB module at a time, including each slot, and see whether the laptop displays anything. Some older laptops have limits on total capacity or on the type of memory they accept, even when the processor theoretically supports more. The 3200MHz rating alone usually should not be a problem because compatible RAM can normally run at the laptop’s lower supported speed, but the modules still need to be compatible with the system.
A RAM upgrade should not normally change whether an external monitor can display an image. Since the laptop’s internal panel is unavailable, the issue may be that this model does not initialize HDMI output early enough for BIOS or boot screens, or that the new memory is failing its memory training even though the machine appears to power on. Confirm the exact RAM type and voltage, test the sticks individually, and reset the firmware settings properly before assuming the graphics drivers are involved.
The original laptop screen has been unusable for years, so I cannot check whether the new RAM works there. With the old memory installed, HDMI output works normally after boot, but with the new kit I get no picture at all.
I tested the system with only one of the new modules, and it still boots without showing anything on the external monitor. The laptop does work again when I reinstall the original memory.