Public Service Announcement: BUY A MORE RAM

[nosser]

ram is really expensive for the intel macs. I just can't afford any right now, even though I can tell that both my imac and macbook pro are starving. Running CS2 sure is fun....

you have a mbp and an cd imac an you're saying ram is expensive! lol kinda funny since you have about $2700 worth of computers and that's only since Feb 06 right, when they came out? I'm just playing, I wish I had a mbp too, I'm waiting for a macbook to replace my pb.

 

[debrey]

According to the buying guide found at the top of this forum:

For AppleCare owners: Your computer must retain at least ONE stick of Apple-branded RAM to continue to qualify with AppleCare. For 12" PowerBook and iBook owners, the logic board RAM satisfies this requirement. For all other computers the Apple-provided RAM must stay with the computer until AppleCare expires.

I assume this is true. If so, you can't just put in 2 Gigs of ram without voiding your warranty.

-- David

 

[WildCowboy]

I assume this is true. If so, you can't just put in 2 Gigs of ram without voiding your warranty.

Sure you can...just keep the original Apple module and put it back in if you have to send/take your machine in for repair.

 

[debrey]

Can someone explain to me how matched Ram works? From what I can tell, it is not enough to have two GB sticks, they must somehow match. What does that mean? Do they have to be bought at the same time (or share a serial number or something)? How much does it add?

Thanks for your help,

David

 

[Xeem]

Sure you can...just keep the original Apple module and put it back in if you have to send/take your machine in for repair.

Definitely the classic Applecare solution; I'd do it with a new (7200 rpm)hard drive with my iBook if I could afford one. Instead, I put the extra money into maxing out my iBook with 1.5 GB and it smokes my dad's 1 Ghz Powerbook with 768 MB RAM (but a faster hard drive and better video card) in almost everything, especially in simple OS X navigation.

 

[lonegeek]

Mac minis only have 1 ram slot?

On a side note....I upgraded from 512 to 1gb of ram in my pc...Didnt notice a differnce..it crashed less for about a month...but now....its back to its "good" old self...

 

[joelypolly]

Having 2 gb is super nice. Never really notice any slow downs except when trying to close bit torrent lol

 

[iSee]

so if i buy a 1gb ram stick to go with my already installed 512 stick, it wont be as efficient? will that at least me more effecient that two 512 sticks?

I poked into this, and this is what I found:

* If your Mac has two DIMMs of the same size and type, memory access will be "interleaved," doubling the memory bandwidth. This goes for the Intel Macs and G5 Macs. From Apple's MBP tech note (the same language appears for each Intel Mac):

The memory controller supports both 512 Mb and 1 Gb SO-DIMMs. However, because the memory in the two slots is configured as a contiguous array of memory, both SO-DIMMs must be the same size and type for the interleaving function to be used to improve performance.

So, how much does this "improve performace?" I don't know. Has anyone found/performed benchmarks? I found some that were for really old Macs (pre-G3 ) showing a 0% - 20% improvement in various tests with an average of 9%. The Macs are so old, though, I don't know if we could expect the same.

Anyway, bdugan, in your case, your single 512MB DIMM isn't interleaved anyway, so you aren't losing anything by adding a 1GB. Would adding a 512MB be better though? It would be interleaved (if its the same "type" whatever that means), but you'd have a 512MB less memory. It's hard to say for sure, but it more RAM ever really a bad thing?

 

[matticus008]

Can someone explain to me how matched Ram works? From what I can tell, it is not enough to have two GB sticks, they must somehow match. What does that mean? Do they have to be bought at the same time (or share a serial number or something)? How much does it add?

Thanks for your help,

David

The RAM must be "matched" as in effectively identical. Same manufacturer, same model line, same timings, same lot number. Even if you have the same speed, same brand RAM, if you don't buy them together, there's a fair chance that a minor revision will break compatibility with dual channel interleaving. The reason that dual channel configurations are faster is that it essentially merges the two sticks of RAM to act virtually as a single RAM array, but with two sets of I/O connections.

This makes 2x512 faster than 1x1024 (because of the greater input/output capabilities), but it fails to achieve the maximum theoretical benefits because there are lots of other factors affecting the setup. Dual channel RAM, however, is rarely faster than simply more RAM. So 1.5GB single channel is still faster than 1GB, regardless of whether it's dual channel or not.

 

[CanadaRAM]

^^ what matticus said. 1.5 Gb unmatched trumps 1.0 Gb matched. There is a benefit to Dual Channel access but I woudn't call it "Much more efficient"

BTW you don't have a choice on PowerMac G5's, they HAVE to have RAM installed in Dual Channel matched pairs

The iMac G5 Rev A and B didn't use dual-channel, but they could implement 128-bit access, a junior version of Dual channel RAM -- it was tested to have a net zero benefit in real world performance.

re: Minis:
The Mini G4 has one RAM socket and is limited to 1 Gb RAM (PC2700 or PC3200)

THe Mini intel has 2 RAM sockets just like the MacBook Pro and iMac intel. All 3 use DDR2-667 SODIMMs

Someone suggested that the Mini intels can use 533 MHz SODIMMs (thus saving $10 or something), and the Mac will underclock to use them... which I think is a stunningly bad idea, especially since the Mini Intel uses main memory for the graphics VRAM, so EVERYthing on screen will be that much slower too...

Thanks
Trevor
CanadaRAM.com

 

[dwd3885]

The Mini G4 has one RAM socket and is limited to 1 Gb RAM (PC2700 or PC3200)

THe Mini intel has 2 RAM sockets just like the MacBook Pro and iMac intel. All 3 use DDR2-667 SODIMMs

Trevor
CanadaRAM.com

they are RAM slots, not sockets

 

[CanadaRAM]

they are RAM slots, not sockets

Definition please?

'Slots' as a term tends to get confused with PCI slots and flash memory slots

- had a customer just yesterday email me that they had two modules in their PCI slots...

 

[yg17]

Hmm, I'm probably ****ed because I sold my stick of Apple OEM RAM for my PB. But, the Magunsun Moss (spelling?) warranty act states that a manufacturer must prove that a non OEM part causes the problem before they can legally void the warranty, so I'd probably be fine if I put up a fight.

 

[indigoflowAS]

by the way...has anyone run into 2GB 667mhz DDR2 SODIMMs yet? i understand that they might be an option on some Dell XPS machines, but i'd like to hear of someone popping in a 2GB chip into their Core Duo iMac/Mini/MBP