Questions about RAM

[Mission]

Hey, i got questions about RAM...

i no there are different types like DDR and SD RAM, but i would like to no the difference between the 2, people say DDR is better, but why? it is faster, etc?

and the speed of the RAM, they have all these names and numbers, like PC 2700, PC 100, PC 133, PC 3200, etc, etc. whats the difference? the higher the PC # the faster? i understand that the speed is like 333 MHz PC 2700 and stuff, the 333 MHz is the speed right? so whats the PC # mean?

if you can sort of clarify this for me it would be great, this is pretty much the only thing i need to know before i cant start building my computer.

Thanks,
MissioN

 

[Circa219]

Good question that deserves a good answer.

SD stands for single data rate and DDR stands fo dual data rate.
The speed of the ram (eg. pc 3200) stands for the MHz of the ram. The higher the number, the faster it is and the more MHz it has. 2700 stands for 333MHz and 3200 stands for 400MHz.

If you are building a computer then I recommend PC 3200 ram. It is faster than said PC2700 ram and you should be able to notice the difference. Also, go for 2 sticks of DDR RAM (eg. 2x256MB sticks.)

I'm building a computer myself and take my advice-READ A LOT! The more you learn, the easier it will become and the better you will understand it. Good luck.

 

[Mission]

yea thanks alot, i thought maybe the numbers had something to do with the motherboard or processor, but i read alot and i didnt see any real connection when displaying the features/specs

i was thinking about getting
Ultra 512MB PC3200 DDR 400MHz Memory 2 Pack
its 1 GB, for like $330 (CDN)...

which is better? to go with for example 2x256 or just one 512? or maybe 2x512 or one 1024? and why?

 

[jaun1477]

SDRAM
SDRAM(S ynchronous Dynamic RAM) is so-called because it can keep two sets of memory addresses open simultaneously. By transferring data alternately from one set of addresses, and then the other, SDRAM cuts down on the delays associated with non-synchronous RAM, which must close one address bank before opening the next
SDR SDRAM
Synchronous dynamic random access memory delivers bursts of data at high speeds using a synchronous interface. Its is actually SDR SDRAM (single data rate SDRAM) but is usually used to referred to as just "SDRAM."

DDR: "Double Data Rate", Refers to RAM. This type of memory can access memory twice as quickly as regular SDRAM

 

[Circa219]

Go with the 2 pack of 512MB. you will be able to run more programs at faster speeds with 2x512 sticks(1gig total) rather then just 512MB of ram.

 

[Mission]

lol well i knew that you could run more with 1 gig of ram over 512 of ram, but which is better? to have TWO 512's or ONE 1024

 

[zerozero]

As to those number PC 3200, 2700 etc.... These represent the number of bits in millions or MBits. since there are 8 bits in a byte, a PC3200= 400MByte/sec 2700=333 etc... just divide the number by 8.
You will also note that depending on the quality of the RAM you will have diferent specs such as 8,3,3,3,
These number represent access time.
Imagine each RAM as a grid with columns and rows and each intersection point being a memory location.
These numbers are CAS and RAS or Column Address Strobe and Row Address Strobe. They represent the number of clock pulses required to access that particular row/column address.
So even if you have 2 sticks working at the same frequency, depending on the brand/quality of the stick it will take more or less clock pulses to access an address point. The lower these numbers, the better.
Since the row and column are not addressed at the same time with row being the first one, another spec is the CAS latency or the number of pulses between a row address and a column address. You can find a little more info here:
http://www.philrees.co.uk/articles/memory_specs.htm
Use any search engine and type your question (e.g. RAM specs explained) and you will end up with several pages giving you info.
Hope this helps

 

[pR3t3nD3r]

2 x 512 MB PC3200 (Trust me).

 

[Mission]

heh, now we have this OC Ram, god so many to choose from. i just stuck with Kingston Dual Channel 2x512 PC 3200 for $305.99 (Canadian)...not bad i think?

 

[mdshort]

Yea, 2x256mb used to be good but has since been outdated, go with a pair of 512mb DIMMs.