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moonmonkey · Mar 15, 2007, 06:25 AM

There used to be a couple of free Ram checkers for macs, little programs that would check the integrity of your installed RAM.

Is there anything free that can still do this?

Thanks.

RAILhead · Mar 15, 2007, 06:30 AM

Your Apple Hardware Test CD should do it, too.

moonmonkey · Mar 15, 2007, 06:42 AM

good thinking!

CMYKid · Mar 15, 2007, 08:59 PM

i dont think i've EVER had the Hardware Test CD pick up on a problem, even really big ones, but I've had really good luck with an Xcode project called Memtest. Very thorough.

Gossamer · Mar 15, 2007, 09:13 PM

You can run Rember, which is a GUI wrapper for Memtest.
But be sure you have tons of spare time, since it takes forever, plus is you've got bad RAM it won't tell you what slot.

besson3c · Mar 16, 2007, 08:28 AM

These memory testing apps work best when you are using as little RAM as possible, they can't test RAM that is locked (i.e. in use). If this will work in Firewire Target Disk Mode or something, I'd definitely do your testing there.

Gossamer · Mar 16, 2007, 09:48 AM

Originally Posted by besson3c

These memory testing apps work best when you are using as little RAM as possible, they can't test RAM that is locked (i.e. in use). If this will work in Firewire Target Disk Mode or something, I'd definitely do your testing there.

Firewire target disk mode makes the primary computer see the one it TGM as a simple hard drive, so that's not very helpful. The best way to do it is run memtest from single user mode.

cgc · Mar 16, 2007, 09:50 AM

I think MemTest has instructions for how to boot into the command line and run memtest.

chris v · Mar 16, 2007, 10:29 AM

Originally Posted by cgc

I think MemTest has instructions for how to boot into the command line and run memtest.

It does indeed have an accompanying read me file. it's quite simple. Drag the Memtest folder to your Applications folder. Reboot, holdoing down command+s. when you get to the prompt, type '/Applications/Memtest/memtest all 3 -L' then hit return.

The three arguments after 'memtest' basically mean check all available RAM, loop the test 3 times (minimum recommended -- you can set this to whatever you want) and the -L tells it to generate a log file when done. If you see FAILURE before it's done running, you can type control+c to stop the program from running, at which point, you'll want to shut down (type shutdown -h now) pull one ram module, then start again.

besson3c · Mar 16, 2007, 11:17 AM

Originally Posted by Gossamer

Firewire target disk mode makes the primary computer see the one it TGM as a simple hard drive, so that's not very helpful. The best way to do it is run memtest from single user mode.

Ahhh.. right, I wasn't thinking.

With our servers here we boot into a CD or floppy disk containing a little Linux kernel that will allow you to run memtest. If you have an Intel based Mac, this should be an option too...

Edit: just read post about booting into the command line. I'd definitely do this, you don't want to be running a GUI for this.