Resolved How to tell if it's a hard drive problem or a RAM problem?

[ravenvii]

Basically I have a MacBook here that's acting up. It'd occasionally refuse to wake up, or sometimes it'd wake up, but goes right into a rainbow wheel of death.

It's clear that the MacBook croaks at those occasions when loading from the pagefile.

It's a common cause of RAM failure, so I promptly tested the 4 GB of RAM in it with memtest. Unfortunately (because it makes things complicated), the RAM passed the tests with no problems. I let it run for three rounds, no problems.

I checked the SMART status of the hard drive, and it's fine. I verified the disk with Disk Utility. All seems fine.

Now, here's my problem: it's clear that the problem stems from the hard drive or the RAM. But I don't want to waste my money buying one part, only to find that it doesn't resolve the problem.

Does anyone have any advice?

 

[BrianBaughn]

You may be right about it being one or the other, but you shouldn't rule out a third possibility: something else.

Does a new user account do the same thing?

 

[Makosuke]

"C) Neither of the above" is, as BrianBaughn says, a possibility, although RAM and hard drive are the most likely culprits. And unfortunately, you've done all the obvious stuff without coming up with anything.

Is this the stock hard drive? If not, I've read of a lot of people having trouble with hangs after sleep due to the drive's internal power management, particularly with WD drives. If it's stock, that's obviously not it.

If you have an external drive handy, I'd recommend trying this: make a partition on it (if you need the rest for backup) or wipe it (if it's a spare) and clone the boot drive to it, then boot from that (preferably after removing the internal hard drive entirely, to rule out it locking up the bus) to see if the behavior still exists. It's clunky with a laptop, but if you can reliably reproduce the behavior by sleeping and waking it a few times, it shouldn't take too long to test.

If the problem still happens, it's obviously not the hard drive, but before replacing the RAM I'd try putting a clean OS install on the external and testing that, just to rule out software.

 

[ravenvii]

I've already formatted and reinstalled OS X, and the problem persisted, so I've ruled out software.

Makosuke - that's a good idea re: external drive. I'll try that - thanks!

 

[ravenvii]

For anyone who cares: it *was* a hard drive problem. Had the HD replaced by Seagate under warranty, and everything's running great now.