Advice RE laptop RAM upgrade

vbimport

#1

I am looking to upgrade my laptop RAM from 1GB to 2GB. At present the laptop takes 1GB DDR2 SODIMM in two 512 MB Modules. I want to push this to 2 GB DDR2 SODIMM in two 1 GB Modules. But looking at whats out there there seems a big difference in prices between different types of DDR2 ram. So what I need to know is what’s the deal with RAM. What’s important for performance. Is one type of memory the same as any other? Thanks.


#2

I have been investigating and as far as I can see, the best you can get for laptops is PC2-5300 633 DDR2 RAM, is this correct?


#3

You don’t have to get higher speed RAM than what’s in there now, cause your laptop probably can’t make use of it anyway. There should be a sticker on your current modules (probably showing 533MHz). First of all make sure that it will actually take 1GB modules (check the manual).


#4

well according to the manual it should take the extra no problem.


#5

to be extra sure , use cpu-z , check the “SPD” tab it will show you info on the ram slots…
http://www.cpuid.com/download/cpu-z-139.zip , anyway better get new ram that exactly same type as your current and also have the same timings to avoid any conflicts


#6

Great link Bunny, thanks. The RAM in there now is running at 266 MHz, is there a major danger of a screw up if I try to put in the PS2-5300 RAM? Also, is the speed difference big?


#7

If you are going to change out the modules go to Crucial and use their memory advisor tool. You enter the information about your computer/motherboard and they will show you what is compatible and what the capacities will be. I’ve never seen these guys wrong yet.


#8

you welcome :slight_smile: , btw incase it wasnt obvious i meant you should check with cpu-z if you have some free ram slots , seems your current ddr2 ram is pc4200 , anyway it will not give you any speed boost whatsoever for two reasons:

a) theres a direct connection between the processor bus speed to the ram ,the ram must be at same bus speed of the processor cuz if it will be lower , well so will the processor speed , for example if the processor bus speed is 200 and you got ddr1 400 which runs at a 200mhz clock that fits fine but if lets say you’d replace it with ddr1 pc4200 which runs at 266mhz clock you wouldnt gain any performance boost why? cuz the processor got everything to do with it the ram can never run at a higher clock speed then the processor bus , so in this scenrio the only way to fully utilize the pc4200 ram to its max or at least close to it is to overclock the processor then its bus will go up… and so will the ram clock speed… , btw the processor bus and its speed (mhz) are two diffrent things , the total mhz is determined by a hardcoded number within the processor (called multiplier) double the original bus speed for example if the multiplier is 9 and the bus is 200 then 9x200=1800mhz or 1.8ghz

b) when you have 2 diffrent types of ram , the “faster” one will automatically be downclocked to the same speed as the “slower” one , they simply cannot run together at diffrent speeds , and as alredy said on a…

you should just buy same type of ram you alredy got , preferably with same timings to avoid conflicts , also to be on the safe side better check on the ram/laptop manufacturer sites that the specific ram your gonna buy was tested 100% working with your laptop , see just cuz you buy a ram that your laptop/motherboard should support it doesnt mean it will like it


#9

Great advice there. much thanks. Also good tip on the Crucial site, thanks DC3. I think I may go ahead and buy the PS2-4200 Spec (btw, I have no slots free, but am ripping out the old 512s and putting in the new 1024s. According to my manual the machine is specd to be upgradeable to this). Anyway, thanks to all for some great help, I think I avoided a big mistake and learnt alot on the way, I can now help friends not to make the same mistake and the world will be a better place. Congrats all, you helped save humanity.