[bigjarom]

I recently added a new 2 GB stick of RAM to my iMac and at first I was on cloud nine. Going from 512 MB to 2.5 GB makes a HUGE difference!

But then almost any time I left my computer on but inactive, the fan would kick into overdrive after about 20 minutes (this happened maybe twice in the last 16 months before the RAM upgrade).

It wouldn't be so bad except that then things have been crashing (Firefox), freezing (Azureus) and quitting unexpectedly (Finder!) when I try to resume activity. Or sometimes the screen saver refuses to be disabled by any kind of input. And earlier today I pressed the power switch to turn the iMac on and instead of booting up there was just a blank screen and the fan running at full-speed.

So I removed the extra RAM and the problems seem to have gone away.

I realize this is most likely a RAM-related issue, but I thought it was weird that it worked fine as long as I was actually doing stuff on the computer, and only misbehaved (due to overheating perhaps?) when idle.

The RAM I got was from Tech Giant and was only $157.65, but it's definitely the right type of PC2 4200..yada yada, and it showed up just fine in the System Profiler.

Has anyone else had a similar experience and if so was it the brand of RAM that was the problem, or was it just a defective unit? Or is there something else I might be overlooking? It's such a pain to have to return stuff.

(And I apologize if this has been covered a million times before.)

-JJ Olsen

[MichiganRich]

Try giving your new memory a few stress tests with the Apple Hardware Test disc that came with your iMac. Booted from that, I've diagnosed bad RAM with it a number of times. FWIW, it definitely sounds like you should be preparing to send it back for warranty replacement.

One of my co-workers swears by Kingston, due to being treated very well by them for returns in the past.

[mduell]

RAM errors are weird, and that's actually a pretty poor price for generic RAM. Return your RAM and buy 2GB Crucial for $145 (my recommendation) or 2GB generic for $105.

[blackslayer]

Hmm...from what i know kingstom ram will keep giving imac users some problems.. Best bet get a hynix ram.

[Veltliner]

Crucial is fine and cheaper than Kingston.