4 GB RAM used with nothing open

wraighty wrote:

Yes I realise that but it has changed recently for no apparent reason so I wondered if RAM does go faulty. I have now reset the PRAM and it looks more like when I installed it and is running much better. Should have done that first, I know. Thanks.

Do you see the 8GB of RAM listed in "About this Mac" or in the Apple System Profiler? I assume you will have two 4GB modules.

Sometimes a PRAM reset needs to be done when new hardware is installed. It really should not be necessary, but it never hurts.

FYI, I find the lower memory slot nearest the bottom case can fail due to broken solder joints from repeated pressure on the center of the bottom case. Also make sure both memory modules are firmly locked in place. Sometimes installing the 2nd module in the lower slot can cause the memory in the upper slot nearest the keyboard to pop loose since the plastic latches are connected to both modules.

You can also test the memory using the Apple Hardware Test or by running Memtest86. You can create a bootable Memtest86 USB disk using Etcher. Option Boot the USB drive and select the orange icon labeled "EFI".

What good is unused RAM doing for you? The system manages RAM to make your computer run efficiently. If you often use certain apps or data the system will preload RAM so that when you access the data it is immediately available. This is how RAM should and does work. Unused RAM is of no value.

If you are having issues with your computer you can try booting in safe mode as a troubleshooting step. If that does not work you can post an Etrecheck report so that we can see what may be contributing to your issue.

wraighty wrote:

I have noticed my MacBook Pro getting slow recently. Even with all apps off about 6GB of my 8GB Ram is being used. I just deleted the hard drive and reloaded Mac OS. Then immediately checked the RAM usage without anything in use except activity monitoring and 4GB is in use.

A few weeks ago I upgraded from 4GB to 8GB and it was great for a while with only 2GB in use with apps off.

Could the RAM itself be faulty?

This seems normal.

If you want to satisfy your curiosity—

To get a good look at your System config. for conflicts or issues, you can run this utility http://etrecheck.com

If you need help interpreting the report you can post it here in its entirety in the "Additional Text" box in the editing toolbar below, in your reply.

You can set its preference to "Allow full Disk Access", with this you get a digest of issues from the last 7 days that are saved in your system.

Memory management for Mavericks and beyond

Here is an in-depth article:

OS X 10.9 Mavericks: The Ars Technica Review | Ars Technica

https://arstechnica.com/gadgets/2013/10/os-x-10-9/17/

Here is a "Glossy" article:

Understanding Memory Pressure in OS X Mavericks

https://www.switchingtomac.com/tutorials/osx/understanding-memory-pressure-in-os-x-mavericks/

Here is a Mantra to help you manage Mac Memory after Mavericks:

"Unused RAM is Wasted RAM"

.