Notebooks & Netbooks

[Thuggins2086]

Acer Aspire 5742Z-4512

Model #: PEW71

OS: Windows 8

Problem: Bought this laptop used with 3 GB of DDR3. Decided to upgrade to the maximum of 8 GB of RAM. I ran CPU-Z to double check the memory type and speed. I logged into Newegg and order my memory. Once I received the memory modules, I installed them, and tried to boot the laptop up. Got to Windows boot logo and it started a reboot loop. Tried all combinations of known good modules with one of each of the new modules. One of the new modules refused to work. I returned it and received another module. That modules also did not want to work. So, my question is this:

What IS the maximum supported memory for this laptop? Why can I go above 6 GB of RAM?

P.S. Yes, I have a 64-bit processor AND OS. Same thing happens when trying to boot from a CD, USB, Media Card reader, or Ubuntu.

[Alan-London]

This is the RAM info from the service guide:

Supports memory size per socket: 4GB
Supports maximum memory size: 8GB
Supports DIMM type: Support DDR III 800/1066/1333Mhz SDRAM
Supports DIMM Speed: 800/1066MHz SDRAM
Supports DIMM voltage: +1.5V
Supports DIMM package: 204pin DDRIII-SO-DIMM

These are the two entries for 4GB RAM sticks:

MEMORY ELPIDA SO-DIMM DDRIII 1333 4GB EBJ41UF8BAS0-DJ-F LF 256*8 0.055UM
Acer Part No. KN.4GB09.001

MEMORY SAMSUNG SO-DIMM DDRIII 1333 4GB M471B5273CH0-CH9 LF 256*8 46NM
Acer Part No. KN.4GB0B.010

[Thuggins2086]

Ok. Both sticks of memory are Team Elite DDR3 1333Mhz SDRAM. Any idea why only one would refuse to work?

[Alan-London · Accepted solution]

From experience gained over many years I can tell you not all RAM (with compatible specs) works in all machines.
Even architecture can make the difference. The Acer parts are both 256x8. While the stated CAS of both matches, do the other timings?
While possibly not the issue here, physical tolerances in socket and RAM PCB can also be problematic causing poor connectivity.
The service guide also covers a number of machines having differing CPUs so it may be worthwhile checking that yours uses one that can support 8GB of RAM.