New ram upgrade - ram is good, but macbook won't start up

Question

Level 1

0 points

New ram upgrade - ram is good, but macbook won't start up

Okay, I've tried searching but have gotten nothing.
I recieved some new ram today, and installed it as soon as possible. However, with 2 x 2gb bits in, it would not start up. I tried reseating them - nothing, just the sleep light [not pulsing] but no sound, no visual displays. I put the old ram back in - it worked fine. I then took 1 of the old ram out, and put 1 of the new ram in, and it turns on and displays 2.5gb of ram.
..wat? I tried it with both, and they definitely work. I know ram has nothing to do with bootup and the bios and whatnot, but what the **** is going on?

Macbook Early 2008, Mac OS X (10.5.8)

Posted on Dec 25, 2009 9:10 AM

Reply

Answer 1

Best reply

Sherman Campbell

Level 2

306 points

Dec 25, 2009 11:07 AM in response to Plexxity

when you install ram, the first time you turn on the computer it can take longer to chime. like a couple of minutes. The computer tests the ram; the more ram, the longer it takes

if it fails to resolve it self.
http://support.apple.com/kb/HT2341
DId you try switch the ram? ie ram in slot 1, move to slot 0. ram in slot 0, move to slot 1. Some times marginal ram will act worse when it's with more marginal ram. think of it like two kids. Ether one is fine by it self, but together they get into trouble. ALso having two different brands of ram can cause issues.

http://support.apple.com/kb/HT1270 lists ram specification

If you bought the ram as an upgrade kit, I would probable exchange it.

You could also try a SMC and NVRAM reset.

Reply

Answer 2

Lyssa

Level 8

41,327 points

Dec 25, 2009 11:31 AM in response to Plexxity

RAM is one of the things that is checked when the computer powers on.

How old is your MacBook? What type of RAM did you get?

The issue you're seeing sounds like you received mislabeled RAM. Even though newer RAM should be backwards compatible, the chipsets in some MacBooks does not accept newer RAM.

You need to return this RAM and get properly labeled RAM.

~Lyssa

Reply

Answer 3

Plexxity Author

Level 1

0 points

Dec 26, 2009 4:15 AM in response to Sherman Campbell

Thanks. I had only waited a couple seconds before when I was like 'aghhh' so I thought this would help. Unfortunately, unless it takes an hour and a half and still doesn't turn on, this is not the problem.

It's an early 2008 model, and the ram I bought was 667hz DDR2. I bought them from the same place, in the same packaging, but yes, I think they are also different makes - different stickers, different layouts of the.. black.. things.

I'm loathe to take them back, but I think that's what I'll need to do. I tried the SMC and the NVRAM resets, to no avail.

I'll update after to see it it's changed anything. Thanks very much.

Reply

Answer 4

Dec 27, 2009 8:56 AM in response to Lyssa

I am having the exact same problem, and I also have ram that is from the same manufacturer but with different physical characteristics (i.e. chip layout, label).

Question: If we do indeed have a mislabeled ram chip, would we see it in any of the configurations in which we have one of the new and one of the old, or would problems only manifest when using them together (i.e. would we see a problem with one of them being mislabeled in one of the bolded configurations below, or only in #6)?

Chip layouts:
1. (OldChip1)(OldChip2) = Works
*2. (OldChip1)(NewChip1) = Works*
*3. (OldChip1)(NewChip2) = Works*
*4. (OldChip2)(NewChip1) = Works*
*5. (OldChip2)(NewChip2) = Works*
6. (NewChip1)(NewChip2) = Doesn't Work

Also, same results when those chips are flipped and in the alternate memory slots.

Reply