Pairing Memory size ? 2

[scorney]

Hello,

I want to upgrade my laptop memory, it's a lenovo T60 type 1952.
I got told the maximum memory capacity is 3Gb RAM and i have 2 slots.
Someone told me to not mix RAM. so for me I would be able to upgrade to only 2Gb.
What would be the issue if I install:
1 x 2Gb SODIMM 200 pins DDR II - 667 MHz and
1 x 1Gb SODIMM 200 pins DDR II - 667 Mhz

I can't understand how it can affect the performance.

Thanks,
Sylvain

 

[wahnula]

Someone told me to not mix RAM.

Did they tell you why?

No doubt it was because dual-channel RAM must be used in matched pairs. Since that's not the case here, use your 3GB.

Tony

Users helping Users...

 

[paparazi]

For the memory to work in dual channel mode the system generally needs to be installed with two identical modules of the same denomination (I have seen instances where two different brands have worked in dual channel but this is not common)
Why dual channel....there is a slight performance advantage but it is small, typically 1-3% (this does vary between platforms so I am generalising)
Will yours run OK with 1 X 1gig & 1 X 2gig yes of course but not in dual channel mode, which as I've said isn't a problem,just that slight performance hit.
What is better.....2 X 1gig or 1 X 1gig plus 1 X 2gig.....
In Xp...probably the matched 1 gig pairing for all users bar the professional vidiographer/graphic artist (there simply isn't any advantage going 3gig with XP for the average user) thats a fact.
In Vista....that's a different story. I would choose the 3gig because Vista's memory usage is just that much higher and that there could be instances where the extra memory outweighs the benefits of the dual channel configuration.
Martin

http://shop.crucial.com/1/4/41091-l...-type-1952-laptop-notebook-memory-module.html

On wings like angels whispers sweet
my heart it feels a broken beat
Touched soul and hurt lay wounded deep
Brown eyes are lost afar and sleep

 

[scorney]

Martin, Tony,

Thanks for your input !!!

I just tried 1 X 1gb + 1 X 2Gb for speed test and I didn't see much of a difference than the 2 X 1 Gb...

I had both here so I was able to try...

Thanks again...
Sylvain

 

[cdogg]

When bandwidth of the dual-channel memory bus exceeds the bandwidth of a CPU's frontside bus, like Martin says you won't see much benefit or notice it if there is one.

However, when the memory bandwidth is less than the CPU bus, you might notice a negative effect from latency. How negative depends on how far below the CPU bus you are. For example, running memory in single-channel at 667MHz wouldn't really hurt an Intel CPU running on a 800MHz FSB. But at 400MHz the negative effect would certainly show.

Fortunately you don't see too many configurations like that out there anymore, so it's not really something to worry about. Newer motherboards with Intel CPUs also have a new feature called Flex Memory Technology which allows two different sized modules to run in dual-channel. The larger memory DIMM will match the other byte-for-byte in dual-channel mode while the remaining memory runs in single channel. You can read more about [blue]Flex Mode[/blue] here:

http://www.intel.com/support/motherboards/desktop/sb/cs-011965.htm#flex

I didn't look up your laptop model to see if it supports flex mode or what the CPU FSB was, but your self test should be good enough to realize that you don't need dual-channel in this situation.

~cdogg
"Insanity: doing the same thing over and over again and expecting different results." - Einstein
[tab][navy]For posting policies, click [/navy]here.

 

[vanka25]

I got told the maximum memory capacity is 3Gb RAM and i have 2 slots.

This seems very unusual, usually the maximum memory that a motherboard can support is a power of 2 - 1GB, 2GB, 4GB, 8GB, etc. My guess is that your laptop actually supports 4GB of RAM - especially if you got it within the last year.

I would go to a site like Kingston or Crucial, enter your model number, and see what they tell you. Be a bit careful though; I purchased an HP laptop with a Santa Rosa chipset a year ago - both both the RAM sites and HP's specs listed the maximum supported RAM as 2GB - exactly what the laptop shipped with. After a bit of research I found out that the Santa Rosa chipset supports up to 4GB of RAM - it took them a bit to update their sites.

 

[Freestone]

http://www-307.ibm.com/pc/support/site.wss/document.do?sitestyle=lenovo&lndocid=MIGR-55644#t

ThinkPad system: T60, T60p
Memory description: PC2-5300 CL5 DDR2 SDRAM 200-pin non-parity SoDIMM
Memory speed: 667MHz
Maximum memory size: 4GB (**)

(**) Windows Vista supports up to 4GB maximum memory (32-bit versions of Windows Vista cannot support 4GB). Windows XP supports up to 3GB maximum memory

 

[paparazi]

But..........getting away from all the technical stuff, what OS are you using? and what applications do you use that are going to tie up so much memory.
Martin

On wings like angels whispers sweet
my heart it feels a broken beat
Touched soul and hurt lay wounded deep
Brown eyes are lost afar and sleep

 

[scorney]

I'm running WinXP Pro.
Using AutoCAD once a while, but the application that I'm running that take most memory is an application that my company build for building database (Oracle) and this is a big consummer....
For the rest is most likely regular application that reguler users use like MS Office...Terminal emulator (Procomm Plus, PUTTY, etc... )

 

[tf1]

This laptop does not support dual channel memory. The Intel T2400 processor has a 667MHz FSB, so the PC2-5300 (DDR2-667) memory modules run at the full FSB speed. So any combination of two modules up to 3GB max total will work.

Regards: tf1

 

[kjv1611]

Thanks, cdogg, for the post about the new Intel tech. I had not read about that to date, that I can remember.

--

"If to err is human, then I must be some kind of human!" -Me

 

[cdogg]

You're welcome.