RAM balancing

[ham61]

I have a question about balancing RAM.
I always thought that it was best to balance what RAM you had in your computer. By that I mean , if you have 512mb RAM then it's better to add another stick of the same 512mb RAM, than say to add a stick of 256mb RAM. Also if you already had a sole stick of 256mb RAM in your computer, you would be best to add 256mb RAM first, before adding further sticks of RAM.I have begun work in a computer shop and my boss tells me this is not the case, but from my own memory I believe it is best practice to balance your RAM this way.Also I received this information from a Geek in a computer shop a year ago, when I upgraded my own RAM.
I'm confused can someone shed more light on this matter?

[digitalocksmith]

It's about a 5-7% increase in performance when you have two RAM modules of the same size and same frequency (MHz) as apposed to alternating sizes.

It's nice to have, but not something you're likely to miss - processor, video card, or hard drive is almost always the bottleneck.

If, for example, you were debating whether to get 2x1 GB or 2 GB (one stick) in any system, for the same price, I'd advise the 2 GB x 1 for the ability to run in dual channel cofiguration which will greatly enhance performance. These separate channels allow each memory module access to the memory controller, increasing throughput bandwidth.

Dont forget though that the major downfall of different RAM speeds in modules configured on the one motherboard is that your total RAM speed will only be as fast as your slowest module.

[ham61]

It's about a 5-7% increase in performance when you have two RAM modules of the same size and same frequency (MHz) as apposed to alternating sizes.

It's nice to have, but not something you're likely to miss - processor, video card, or hard drive is almost always the bottleneck.

If, for example, you were debating whether to get 2x1 GB or 2 GB (one stick) in any system, for the same price, I'd advise the 2 GB x 1 for the ability to run in dual channel cofiguration which will greatly enhance performance. These separate channels allow each memory module access to the memory controller, increasing throughput bandwidth.

Dont forget though that the major downfall of different RAM speeds in modules configured on the one motherboard is that your total RAM speed will only be as fast as your slowest module.

Thankyou for your very informative reply. I have a situation where a 256mb RAM has been added to a stick of 512mb. Therefore from what you have said the RAM speed will only be as fast as the 256mb RAM, which I gather from your first sentence may be about a 5-7 % decrease in performance.
What happens if 2 sticks of RAM are different frequency (MHz) is it the same outcome
(5-7 % decrease in performance).

[digitalocksmith]

A 256 added with a 512 will still give you a total capacity of 768mb of RAM, however if the sticks are of different frequency, then overall speed of the combined RAM will be only as fast as the slowest frequency stick.

The main reason why some users dont like to mix and match RAM capacities and Frequencies is because of Compatibility issues.
Some Motherboards can be very 'picky' about what RAM is installed and many dont even like different manufacturer mixes.

Every Motherboard on every system is different and unique in its own way so what has worked for some, may not work for others and visa versa.

I have had systems that wont even POST after new RAM has been added of a different brand but same capacity and frequency.....and when i shutdown and changed DIMM slots, it booted up.....go figure?

Its a strange business we deal in with computers...hehe!

Regards

[ham61]

Yes dealing with computers, certainly is a complex business and I am trying to gain as much knowledge as possible. My boss(owns the computer shop) does not have the time to impart all his knowledge and sometimes I wonder how accurate it is anyway. Basically he told me not to worry about adding different size sticks of RAM, as it was him that added the 256mb stick to the 512mb one. When the customer left this computer in our shop for me to repair. I diagnosed a faulty power supply (replaced) , but then it was still having issues starting smoothly. I troubleshooted the motherboard and I narrowed it down to the fact that if I removed the 256mb of RAM the computer booted and ran smoothly. When I told the boss about balacing RAM, he hit the roof! because he said, "It was me that sold her that RAM and installed it!"
He gave me a short lecture on RAM (his version) only to say that all that mattered was whether the motherboard was single channel or dual channel. Older motherboards he tells me are single channel and it doesn't matter if the RAM is not balanced, but the new motherbards are dual channel and two sticks of RAM must be matched exactly. Somehow I suspect there is a lot more to it than this. Either he's not telling me or he doesn't know and is afraid to admit it.
That's why I've turned to you guys, my anonymous computer geek friends, out there on the internet..........
Thanks guys for your interest and help in my thread (lifeline)
Please feel free to add all you can on the mysteries of RAM
I grew up on a sheep farm, owned by my Dad, and he'd tell you there was no mystery to the Ram there. Some parts are similar tho', like, you add more ram, bigger and faster and ewe end up with better output. :)

[jermaghs07]

i can't take all the Sheep puns.....

IF the ram is DDR2 it needs to be the same size and preferably the same brand. if it is not DDR2 then it won't really matter that much. you do get a small performance increase when you synchronize your ram but it won't matter that much.

[the_witt]

I have a related question...What happens when you put more RAM on the board than what the specs say?
We have an IBM system that says it maxes out at 256K (I know, but its a POS machine)
What would happen if we put in.. say more than that?

[jermaghs07]

you would probably get an error the first time you started up your machine. they have a max ram capacity for a reason

[satyapanda]

i have intel 915 gav motherboard ,earlier i had 256 mb transcend ram ....but after sometime i bought a 512 ram of simtronics and installed ...both are of same frequencys (400MHz) ...but after installing the 512 ram ...when i saw in my bios system was showing 768 mb of memory and speed 333MHz ....how should i increase the speed to 400MHz

[rentalsolutions]

hi thank you for sharing very informative thread but i have one question that if you are using Celleron processor and i have buy 1 GB ram but still my pc speed in sooo low...why...?