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Crown16

macrumors regular
Original poster
Mar 10, 2008
110
0
Hi, i have a imac 2.00ghz intel core 2 duo and i bought some extra ram for it(1x 1gb 1x 2gb) at macsales.com problem is that they wont work when there both in my mac. i can put one in doesnt matter which slot and my mac will just boot normally. but when i put them both in it starts and the screen just stays black and the little light is on. ive tried all the combinations but i cant find a problem. I dont think the slots are broken cause they both work eventhough i only have one ramstick in the mac. and both ram sticks work aslong i use them seperately.
 
Hi, i have a imac 2.00ghz intel core 2 duo and i bought some extra ram for it(1x 1gb 1x 2gb) at macsales.com problem is that they wont work when there both in my mac. i can put one in doesnt matter which slot and my mac will just boot normally. but when i put them both in it starts and the screen just stays black and the little light is on. ive tried all the combinations but i cant find a problem. I dont think the slots are broken cause they both work eventhough i only have one ramstick in the mac. and both ram sticks work aslong i use them seperately.

Question #1. What RAM specs does your Mac call for, and what RAM did you buy?
 
Hi, i have a imac 2.00ghz intel core 2 duo and i bought some extra ram for it(1x 1gb 1x 2gb) at macsales.com problem is that they wont work when there both in my mac. i can put one in doesnt matter which slot and my mac will just boot normally. but when i put them both in it starts and the screen just stays black and the little light is on. ive tried all the combinations but i cant find a problem. I dont think the slots are broken cause they both work eventhough i only have one ramstick in the mac. and both ram sticks work aslong i use them seperately.

Intel Macs use dual channel memory. It looks like you bought a 1GB stick and a 2GB stick...that configuration isn't going to work. You need to install identical pairs of RAM. The literature on dual channel memory states that it will work without identical pairs. In theory, it should. In practice, it doesn't.

also, if your iMac was one of the models released prior to late 2006, chances are it only supports 2GB of memory.

try installing two 1GB memory sticks...that should work. You might want to check the Apple website to see if your model will address 4GB.
 
Intel Macs use dual channel memory. It looks like you bought a 1GB stick and a 2GB stick...that configuration isn't going to work. You need to install identical pairs of RAM. The literature on dual channel memory states that it will work without identical pairs. In theory, it should. In practice, it doesn't.

also, if your iMac was one of the models released prior to late 2006, chances are it only supports 2GB of memory.

try installing two 1GB memory sticks...that should work. You might want to check the Apple website to see if your model will address 4GB.
I've never had any problems on my Macs using unmatched pairs.


Understanding Intel Mac RAM - Mac Guides
 
Intel Macs use dual channel memory. It looks like you bought a 1GB stick and a 2GB stick...that configuration isn't going to work. You need to install identical pairs of RAM. The literature on dual channel memory states that it will work without identical pairs. In theory, it should. In practice, it doesn't.

that is false. you can use different sized ram sticks.....i know as ive done it with my macbook
 
I have yet to see with my own eyes this configuration run reliably on an Intel Mac.

like i said it works:cool: stop spreading misinformation

i used to run my mb with these configs...slowly getting to max ram it could handle

256 and 256
256 and 512
512 and 1 gig
1 gig and 1 gig

all of these were flawless in terms of funtionality


HOWEVER, you can only get dual channel benefits if they run at the same size. but you can run different sized sticks with out issue
 
like i said it works:cool: stop spreading misinformation

i used to run my mb with these configs...slowly getting to max ram it could handle

256 and 256
256 and 512
512 and 1 gig
1 gig and 1 gig

Comp/TIA A+ Certified Technician :cool:

I have seen it fail many more times than you have seen it succeed. It's not misinformation, it's hard won experience.
 
Comp/TIA A+ Certified Technician :cool:

I have seen it fail many more times than you have seen it succeed. It's not misinformation, it's hard won experience.

oh please many here have had it work without issue hence why its also in the link thats been posted in this thread
http://guides.macrumors.com/Understanding_Intel_Mac_RAM


it IS misinformation pure and simple

Dont have me drag CanadaRam into this haha
 
Intel Macs use dual channel memory. It looks like you bought a 1GB stick and a 2GB stick...that configuration isn't going to work. You need to install identical pairs of RAM. The literature on dual channel memory states that it will work without identical pairs. In theory, it should. In practice, it doesn't.

also, if your iMac was one of the models released prior to late 2006, chances are it only supports 2GB of memory.

Wrong and Wrong.

Dual channel configurations are NOT mandatory. They give a modest speed boost (6% - 8%) but mismatched RAM is perfectly fine (as long as both SODIMMs are good modules, of course)

Intel Core2Duo machines all support the use of 2 GB SODIMMs. The difference is whether they can utilize all 4 GB. The Santa Rosa models can. Pre-Santa Rosa models are limited to recognizing 3 GB. Only the CoreDuo models are restricted to 1 GB SODIMMs.

(Just for S & G, I took out a 2 GB SODIMM and installed a 2 GB and a 1 GB in my pre-Santa Rosa MacBook. Guess what. It works.)
 
Never had a problem on any of my Intel Macs (2 iMacs, a MacBook and a mini all of which have run mismatched RAM at some point). Never heard of anyone having a problem on this board. If it were a widespread issue, we would have heard about it here.
 
all i can say is im glad we have other knowledgeable members to give correct information.

ever occur to you it may be the user who
1) cant install their own ram and might f it up
2) you fix computers which of course have issues
3) you realize #2 and attribute it to ram and more specifically mismatched ram lol

while bad ram can cause a computer to fail, it is not because its mismatched

i guarantee that if you install mismatched ram in an intel mac it will work.

these forums are always complaining about computers be it case craking, staining, displays etc. i have never seen a thread on mismatched ram not working. that should be ALL the real life testing you need...especially when so many run it with mismatched sticks
 
Comp/TIA A+ Certified Technician :cool:

I have seen it fail many more times than you have seen it succeed. It's not misinformation, it's hard won experience.

My own personal experience and everything I've ever read on the issue suggests that the only difference in matching pairs of RAM is the slight performance boost from dual-channel performance.

Non matched pairs obviously equals no dual-channel.

However, to say that mismatched pairs will not work on an Intel Mac is misinformation plain and simple, all your certifications and personal experiences aside. ;)
 
You know the ONLY time I have ever encountered this issue is with some of the off brands of ram. They seem to not play nice with some other brands of ram. I have run mismatched ram for many years, and it does work. Just not with all brands. Get another stick of ram as your 2gb, and it will work.
 
wow, lots of replies! I bought the ram at macsales, before i bought anything i was sure to check everything out since i live in the netherlands and bought it in the us. first i know that 2 of the same modules works better, or so they say. and i know my mac can handle the 4gb but it wil only use 3gb. so i went to my local mac store. and they verified this. they also said they could in stall 2gb of ram for me for the small price of 300€. yeah right like im some tard. im no computer whiz but i know that aint a fair price.(it has the same price on the apple site btw) Im gonna pop into the store some time this week see what they think of it. ive reset my smc with command option p r didnt see any differance. how ever i dont see why macsales would sell me a 1gb module and a 2gb module if they know exatly (gave them specs) what kind of computer i have. and i have a guarantee hear somewhere:p so if all my sources of help dont know it anymore ill just have to let macsales send me a 2gb module extra. thanks for all the help so far guys
 
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