I have a MacBook 2008 that used to run OS X beautifully. But then it stopped working correctly, it wouldn't always boot. When it does it is always super slow, or you get the rainbow wheel of death for hours. I have put elementary OS on it before and it ran very well! But his time it seems to run just like OSX does. So is this a software issue or a hardware issue. If hardware how do I fix it?
On a 2008 MacBook Pro I would suspect a failing hard drive, or at least multiple bad blocks. The 2008 should have come with a bootable DVD. You can boot from that and run Disk Utility to check the hard drive.
An SSD is a very worthwhile upgrade, as well as additional memory. I would consider these upgrades, even if the drive tests OK.
I would suggest testing your RAM and hard drive for errors. I'm not sure if this will work since you have already loaded elementary, but you could try to run the apple hardware test described in this article http://www.macissues.com/2014/03/21/how-to-run-and-interpret-apples-hardware-tests-on-your-mac/:
To invoke the hardware tests, insert the restore DVD that came with your system. If your system is new enough that it did not come with a DVD drive, then skip this step. Now perform the following actions:
- Reboot your Mac
- Hold the “D” key down immediately when you hear the boot chimes