New iBooks - which RAM?

MalcolmR

macrumors newbie
Original poster
Jun 30, 2005
21
0
London, UK
Has anyone got any idea whether it's possible to buy 'guaranteed compatible' RAM from Crucial (UK) for a new 12" iBook at the moment?

Their 'memory advisor' is great, but it's still only recommending PC2100 memory (the new iBook comes with PC2700).

Oh, by the way: New iBooks next Tuesday? ;)
 

ITASOR

macrumors 601
Mar 20, 2005
4,400
3
Didn't the old iBooks have 2100 RAM, but could take 2700 because it clocks down?

Would it be correct to say they now have upgraded them to use 2700?
 

Mitthrawnuruodo

Moderator emeritus
Mar 10, 2004
13,604
146
Bergen, Norway
The (new) iBook uses "512MB PC2700 (333MHz) DDR SDRAM; supports up to 1.5GB; 1 available expansion slot" according to Apple. Which means you cannot use 2100 RAM because the RAM can only scale down and not up...
 

grapes911

Moderator emeritus
Jul 28, 2003
6,943
3
Citizens Bank Park
A little off topic, but I figured I give an analogy of "clock down" in case anyone was confused (it took me a while to understand it).

The terms 2100, 2700, 3200, (there a many more too) are used to differentiate the different speeds of RAM. They aren't absolute speeds though. They are the safest max speed the ram can go. If a computer sends info to the RAM at 2700 speeds, then obviously the 2700 can understand it. The 3200 is able to understand it because the info is coming slower than the maximum speed it can read. The 2100 will struggle to keep up and will probably fail (The computer probably won't boot, but I'm not 100% sure).

Think of RAM as a car. Just because CAR-A can go 180 miles/hr, doesn't mean it can't go 100 miles/hr or 1 mile/hr. But if CAR-B can only go 70 miles/hr, then it has no chance of going 100 miles/hr.
 

dsharits

macrumors 68000
Jun 19, 2004
1,639
0
Plant City, FL
grapes911 said:
A little off topic, but I figured I give an analogy of "clock down" in case anyone was confused (it took me a while to understand it).

The terms 2100, 2700, 3200, (there a many more too) are used to differentiate the different speeds of RAM. They aren't absolute speeds though. They are the safest max speed the ram can go. If a computer sends info to the RAM at 2700 speeds, then obviously the 2700 can understand it. The 3200 is able to understand it because the info is coming slower than the maximum speed it can read. The 2100 will struggle to keep up and will probably fail (The computer probably won't boot, but I'm not 100% sure).

Think of RAM as a car. Just because CAR-A can go 180 miles/hr, doesn't mean it can't go 100 miles/hr or 1 mile/hr. But if CAR-B can only go 70 miles/hr, then it has no chance of going 100 miles/hr.
Good analogy. I like it. :)
 

dcv

macrumors G3
May 24, 2005
8,021
1
You need to buy PowerBook RAM (as posted by others above)

PowerBook RAM is more expensive though - just checked the Crucial UK site and looks like the price has increased in the last week or two. It was £123 for the 1GB, now it's £133

(compare this with just £88 for 1GB for the iBook prior to today's revision) :eek:
 

realmcenter

macrumors member
Jul 10, 2005
51
0
Denver, CO
My 12" iBook came with PC2700 RAM despite only needing PC2100 memory. The new iBook 12" bus speed is the same as the old one, so PC2100 memory should work just fine. Apple probably used PC2700 memory since they buy it in huge quantities and the price difference between PC2100 and PC2700 RAM is very small and in the quantities they are buying, likely nonexistant. It seems the 14" iBook will require PC2700 memory, though.