Apple hardware test

The original installer discs are needed to run the hardware test. Contact AppleCare to see if they might still have it for your machine. If not, finding them outside is difficult, unless you know someone from a usergorup who has exactly the same age machine you do. http://www.apple.com/usergroups/

If all you need is a memory test, Rember has all the versions you need on its page. Just scroll down if you can't find the one you need at first.

Be aware memory tests that don't give you any result are inconclusive, and you could still have bad memory. Memory tests that give you errors, mean you must meet specs. Only http://www.macsales.com/ and http://www.crucial.com/ do I know will give you specs by the model and age of the machine, and not just by physical properties. Anyone who does must also give you a lifetime warranty to be considered worth while. Kingston's ValueRAM is to be avoided.

The replacement chips themselves have a fairly good warranty, once they are proven to be the cause of a problem and are removed from the computer so as to facilitate an eventual exchange for another set of chips.

{This exact situation can be the rub, because while the machine is part, is when you need to replace bad RAM; not three weeks later when the warranteed RAM arrives in the mail. Or you find the RAM was on sale because they aren't going to re-stock older RAM, and you got a great deal. An authorized Apple reseller's service department did that to me and my then-new iMac G4, under Applecare, and put in a Kingston chip. Once I loaded applications and did like, eight things, I could make it kernel panic everytime. This went on for about 7 months and a few thousand miles of driving to bring the new iMac into the authorized service, to have them keep it a week, and I'd get it, drive home 200 miles, to find I could repeat the same steps to kernel panic it. Later on, the chip was no longer available once it was decided they were at fault. By then the in-store warranty on replacement of that RAM was no longer valid, and they didn't have any other RAM, and no kingston. So I bought a replacement chip of another brand, $150. and they installed it that day. By then, their allegedly Apple trained service persons messed up two logic boards and the computer has been dead a few years. A lesson.}

Oh, User Groups are usually local owners of a similar product brand and they get together at times in person and share horror stories. Kinda like trick-or-treat, only more often. Costumes are optional & so are treats. LOL Some even have OK web sites.

So like those impossible commericals where fifteen things go wrong, and the suggestion goes insane, which is what happened with the only new car I've ever owned... same as the iMac, had dozens of them I could fix myself. got the new iMac, got rid of the others. bought iBook while iMac was in shop forever. it still works. This taught me to not rely on sealed products with magic inside, that also scares me away from new Macs.

The 'slight graphics problem' may be due to some solder joints on the logic board or the built-in GPU starting to fail. Does the symptom of graphic issue go away if you use an external display?

Good luck & happy computing! 🙂