Adding more RAM

[whitewater]

So i have a imac late 2009. it has 2 2g slots full. I can put 2 more in. I bought 2 4g plug ins. I put them in and when i turn on my computer it doesnt turn on it just beeps. a single beep. I took one out and then it was 2 beeps, i exchanged them and tried different figurations with the 2 slots.

everything is clean in there.

When i bought them i made sure they matched the specs..

I did a search online and really did not find out much info..

Just wondering if anyone here had any.

thank you in advance.

[Admiral]

Needs to be the same ram size as well, can't mix that.  You have a 64 bit operating system right?  Go with 4 sticks of 4GB.

Also try just the 2 new sticks in the same spots the first ram was in alone.  If that doesn't work there must be something wrong with the ram / timings configuration.

[Sbrem]

Call your vendor too, they can probably help. Usually adding RAM to a Mac is pretty easy (except one we bought a year ago with the RAM soldered to the  board!!!!)

Steve

[whitewater]

they fit, and go in alright. it shoudl be a plug and play, my guy here did it to his computer and worked right away.

If i take out the original one and put in the new one, will it mess up computer at all?

[GraphicDisorder]

You will want to be sure your computer will accept that ram. Just because the ram fits doesn't mean it will work, some boards max out at X number of total ram. So if your board was say a 4GB max system, then you can't go off and put 8GB in it.

Have you tried just 1 of the new ram sticks? Just to see if it boots?

[whitewater]

You will want to be sure your computer will accept that ram. Just because the ram fits doesn't mean it will work, some boards max out at X number of total ram. So if your board was say a 4GB max system, then you can't go off and put 8GB in it.

Have you tried just 1 of the new ram sticks? Just to see if it boots?

yes i tried 1 stick in each one and different configurations.

when i looked up my model it said 2 4g will work. 

i may send these back and get 2 g instead to see if it makes a difference.

[ebscreen]

Bad ram out of the box isn't that uncommon. The stuff is fairly sensitive.

[GraphicDisorder]

Need to be clear here what you have done so we can understand what you have.

The computer has 4 slots, 2 slots with 2gb sticks in it, 2 empty, correct?

You have then added the 2 new 4gb sticks leaving the 2gb in, correct?

Have you removed the 2gb sticks and only tried the 2 new 4gb sticks?

Have you tried just using 1 new 4gb stick only, nothing else?

Various things could be going on here. Bad ram, while unlikely BOTH to be bad it could be the case and I have seen it. Some motherboards would require all sticks to match, exactly the same size...so you may not be able to run the 2 different sizes. You can try each of the above configurations basically and see whats what report back.

[whitewater]

Need to be clear here what you have done so we can understand what you have.

The computer has 4 slots, 2 slots with 2gb sticks in it, 2 empty, correct?

You have then added the 2 new 4gb sticks leaving the 2gb in, correct?

Have you removed the 2gb sticks and only tried the 2 new 4gb sticks?

Have you tried just using 1 new 4gb stick only, nothing else?

your correct on everything..

I did not take the 2 original out, because i was not sure if that would mess anything up.
Tonight when im through for the day ill take the original out and put in the 4g and see.

thanks

Various things could be going on here. Bad ram, while unlikely BOTH to be bad it could be the case and I have seen it. Some motherboards would require all sticks to match, exactly the same size...so you may not be able to run the 2 different sizes. You can try each of the above configurations basically and see whats what report back.

[GraphicDisorder]

I bet you pull the 2 x 2GB and replace with the 2x4GB it works.

That will double your ram up, id then look into if your mother board specifically can even hold 16gb of ram. GENERALLY speaking if a motherboard will read a 4gb stick and it has 4 slots it will accept one in each, so you'd be all green to go get 2 more 4gb sticks, but id look it up to be sure.

[ixpoz]

It sounds as though you’ve covered your bases with trying different configurations. One resource that I use is a site called macsales.com, they have a very good ram configuration on their site for macs. Their prices are very reasonable as well.

[Chadwick]

I don't use or fix macs, but your ram with that generation of cpu and such should run dual channel,
similar to most PC configs if I am not mistaken.

For example, on a regular PC motherboard with 4 ram slots, 2 slots will be one color, 2 will be another.
( some boards are not as friendly and you need to read the manual to figure which is which )

With 2 sticks of ram, you put one into each channel.

So with mismatched sizes of ram sticks, I believe you would put one of each size into each channel.

Channel A: 2gb+4gb
Channel B: 2gb+4gb

Balance.

The beep is telling you something. Beep codes help you troubleshoot.

I found this with a quick search:
https://mediawiki.middlebury.edu/wiki/LIS/Apple_Computer_Beep_Codes

But I would do some research into your specific model.

Best luck.

[Chadwick]

And now ya got me thinking...

Check the voltage on your new ram, should be clearly marked on the sticker.
It must match what you have.

Another 'beep' code list:
http://www.idownloadblog.com/2016/02/25/mac-os-x-startup-tone/

[1964GN]

There are a few models of late 2009 iMacs. I would go here and read up on your specific model/processor combo https://everymac.com/actual-maximum-mac-ram/actual-maximum-imac-ram-capacity.html