Q: Problems with newly installed RAM

3 beeps means ther is a problem with the RAM.

Who did you buy the RAM from.

Macs are picky about RAM.

You just can't buy Mac RAM from anywhere.

Buy RAM from Crucial Memory or OWC.

The other issue is that your iMac can only take 6 GBs of RAM Max.

So, if you have matching pairs of 4 GBs each, this will not work in this iMac as the iMac is not liking not seeing the extra 2 GBs it can't access.

You need to a 4 GB stick and a 2 GB stick with these specs.

Memory Slots     2 - 200-pin PC2-6400 (800MHz) DDR2 SO-DIMM

One of the sticks maybe defective.

Isolate which one cause your iMac to not start and use your original 1 GB stick with the good 2 GB stick.

If that gets your iMac running for now, use this config, call OWC, return the defective stick for a replacement.

RAM can and does go bad, even initially.

When you return the defective stick, instead of a replacement 2 GB stick of RAM, order a 4 GB stick, instead.

4 GBs of RAM for running OS X and additonal applications is a working, bare minimum RAM.

Your iMac won't really run any better on 4 GBs.

Install a 4 GB RAM stick to give your iMac a total of 6 GB.

You iMac will run much better.

While iMacs do perform better with matched pairs of RAM any minor performance increase with paired RAM is not going to be as big of an improvement as having 2 GBs of extra RAM.

In case you're not installing the RAM properly here's an Apple link to the procedure

http://support.apple.com/kb/HT1423#2

Also another note, make sure when handling the RAM sticks that you do not touch the bottom of the sticks that have the gold connector bars at the bottom. Handle Ram from the sides.

Sounds like maybe the modules are not fully seated in the slots. Lay the iMac face down on a soft cloth as per the instruction in iMac: How to remove or install memory and then push real hard on each module with both thumbs to make sure that they are firmly seated in the slots.

Hi artnsus, I will make this simple for you. I bought 16 gigs of ram from OWC. One stick went bad in a matter of a few days. The grey screen and 3 dong sounds is a a bad stick. The other guy is right, Apple computers are very picky about their ram. I ended up with a kernel panic as well. That's was real fun! Let me say that again. That was not fun! So, here is exactly what OWC emailed me and said I should do after I install ram in my Mac,

Gently clean the memory contacts with a soft pencil eraser and make sure you seat them properly into the slots.

Resetting PRAM and NVRAM (should be done any time you alter the ram configuration)

   1.    Shut down the computer (should already be off from install)

   2.    Locate the following keys on the keyboard: Command, Option, P, and R. You will need to hold these keys down simultaneously in step 4.

   3.    Turn on the computer.

   4.    Press and hold the Command-Option-P-R keys. You must press this key combination before the gray screen appears.

   5.    Hold the keys down until you hear the startup sound ("bong") for the third time.

   6.    Release the keys.

Let me say this, nowhere in Apple's Instuctions of adding or replacing ram does it say anything like this needs to be done! I don't really get this and to be honest I don't trust buying ram from OWC. Oh, let me also say this. OWC also said that my iMac could take up to 32 gigs of ram while Apple specifies only 16. They say they do testing but they failed my test and honestly I don't see myself doing much business with them again. That's not to say they are to a good company, I just don't think I want to by ram from them again.

Sorry to hear you've had a bad experience - contrary to yours, I will not buy RAM anywhere else. I've never reset PRAM while swapping memory; here is a kb article on what type of info is stored and, as you can see, kernel panics are mentioned so the instructions were most likely related to your kernel panic, not the RAM.

The 3 beeps are the indicator of issues with the RAM.

Have you made sure the RAM is locked into their slots.

There is some resistance when plugging them in.

They just don't go into their slots easily.

Maybe after you're sure they are locked into their slots, try an PRAM and NVRAM reset as a previous poster suggested.

After you initially power on the iMac, quickly hold down the Command, Option and P and R keys simultaneously wait for the startup chimes to chime 3 times, then let these keys go and see if the iMac will boot up normally.

artnsus, when I went through my issues with apple they said that it could be a number of issues. If the original ram is indeed working as it should then the problem could be with other hardware in the computer. What you need to do is trouble shoot this logically. First work with what you had originally that worked. Make sure you are seating the ram completely. Like MichelPM stated above, 3 beeps means that one or both cards is bad. Try removing only one card and see what happens. From what I am getting the original ram is no longer working either. Also, get on Apple.com and look up the exact specifications for your particular model. Also look up the instructions for installing ram in your machine. Above all else dont get fustrated. Think through everything you have done up until this point and work logically from there. I wish you the best. and if I can help then just ask.