DDR II Memory compatibility

[mrique]

Hi there
I have a laptop with memory specs : DDR II PC3200 400 Mhz
Can I put other DDR II type with upper frequency (eg PC 53000 or
other) ? will it work ?
Thks

 

[Paul]

Hi there
I have a laptop with memory specs : DDR II PC3200 400 Mhz
Can I put other DDR II type with upper frequency (eg PC 53000 or
other) ? will it work ?
Thks

Faster memory is compatible with slower applications. If the
laptop uses DDR2-400, you could use DDR2-533 or DDR2-667 in
it.

You can confirm the options for your laptop, by visiting
crucial.com or kingston.com and searching for your laptop
there. They will normally show a whole range of memory
modules that would work, with some of them being much
faster than they need to be. Because the speed is backward
compatible, the faster ones can be used in place of a slower
one.

To get the "PC2" number, you multiply the DDR2 number by 8.
So DDR2-667 becomes PC2-5300. The marketing people like numbers
with zeros on the end, as they're easier to remember.

Paul

 

[d6nish]

Faster memory is compatible with slower applications. If the
laptop uses DDR2-400, you could use DDR2-533 or DDR2-667 in
it.

You can confirm the options for your laptop, by visiting
crucial.com or kingston.com and searching for your laptop
there. They will normally show a whole range of memory
modules that would work, with some of them being much
faster than they need to be. Because the speed is backward
compatible, the faster ones can be used in place of a slower
one.

To get the "PC2" number, you multiply the DDR2 number by 8.
So DDR2-667 becomes PC2-5300. The marketing people like numbers
with zeros on the end, as they're easier to remember.

Paul

Hello,

What if I have the motherboard that takes DDR400 PC3200 only can I put
533 Mhz memory in it?

Thanks
dG

 

[RobV]

Hello,

What if I have the motherboard that takes DDR400 PC3200 only can I put
533 Mhz memory in it?

Thanks
dG

DDR400 PC3200 memory is the last SDRAM memory that was around when DDR2
memory came around, and that's already giving way to DDR3 memory.

I don't think the memory you have is DDR2, as PC3200 runs at 400 MHz
(effective). With two DDR PC3200 memory modules installed, some MBs
will run in Dual Channel mode, which grabs more bits per cycle than
single channel, which speeds up memory transfers.

The point is, none of these are interchangable. Installing faster
memory alone will not change anything unless the CPU and/or memory
busses can run faster to take advantage of it.

 

[Paul]

Hello,

What if I have the motherboard that takes DDR400 PC3200 only can I put
533 Mhz memory in it?

Thanks
dG

You are mixing technology types. You can't do that.

Be careful with the nomenclature. PC3200 and DDR400 are terminologies
for DDR memory. On the desktop, that is a DIMM with 184 pins, and a 2.5V
power supply.

PC2-3200 and DDR2-400, would be terminologies for DDR2 memory. On the
desktop, that is a DIMM with 240 pins, and a 1.8V power supply.

To be interchangeable, the memory would have to be in the same
family. A DDR2-533 DIMM could be used in a DDR2-400 application,
as the faster stick is compatible with the slower application.

For DDR memory, there were a few enthusiast memories that went above
DDR400. The record, is somewhere around DDR600. You could take a
DDR600 memory and use it in a DDR400 application. But that would be
a terrible waste, since the purchase price for the memory in question
might have been quite high. There are probably some DDR500 memories
or thereabouts, that could also be used in a DDR400 (184 pin) application.

What you cannot do, is jam a DDR2 stick in a DDR slot. Or vice versa.

Paul