Sd - Ddr - Rd - Huh?

[dubstar]

ok, so SD is slower than DDR, but why does RD sound so different to me.. I've never really heard of this before, is it new?

 

[NetRyder]

Some info from an online paper:

What is SDRAM?
SDRAM is a technology in which a clock is used to Synchronize the timing of the
memory with the CPU. This greatly enhances the performance of the memory. SDRAM
also uses two banks. This allows one bank to be accessed while the next bank is
preparing to be accessed. This increases the speed at which SDRAM can operate for it
allows a new memory accesses before the preceding access is completed.

What is DDR Memory?
DDR memory, or Double Data Rate memory, is an evolutionary new memory technology
that doubles the data though put to the processor, or CPU. It is an evolution of PC133
SDRAM, which leverages the existing production and environment to provide higher PC
performance.

What is Rambus Memory (RDRAM)?
Rambus is a chip to chip interface design that is system wide, allowing 600 MHz transfer
rates. It allows data transfer through a simplified bus that operates in a high frequency
range. Rambus uses a low voltage signal swing with data transfer on both edges of a
synchronizing clock pulse. The Intel Pentium IV CPU is designed to take full advantage
of this new, extremely fast memory design

 

[dubstar]

so RD RAM kicks more butt than DDR RAM which kicks more butt than SD RAM which kicks more butt then RAM.

very clear to understand, thankyou NetRyder.

what about PC3200, PC2700, PC2100, PC1600, Non-EEC DDR.. what is up with those? whats the difference, are they pretty much all interchangable with each other, is 1 faster than the other? can i have 1 PC3200 and 1 PC 2100 in the same computer?

thanks.

 

[NetRyder]

Originally posted by dubstar
so RD RAM kicks more butt than DDR RAM which kicks more butt than SD RAM which kicks more butt then RAM.

All of them are different types of RAM ... so to end your statement, it would be SDRAM kicks more butt than EDO RAM.

 

[NetRyder]

Originally posted by dubstar
what about PC3200, PC2700, PC2100, PC1600, Non-EEC DDR.. what is up with those?

PC3500 (DDR433) = 433MHz
PC3200 (DDR400) = 400MHz
PC2700 (DDR333) = 333MHz
PC2100 (DDR266) = 266MHz (which was two times the speed of PC133 SDRAM @ 133MHz, hence the name DDR or Double Data Rate)

 

[NetRyder]

Originally posted by dubstar
very clear to understand, thankyou NetRyder.

You're welcome

Cheers!

 

[dubstar]

what in the world is EDO RAM??

Originally posted by NetRyder
All of them are different types of RAM ... so to end your statement, it would be SDRAM kicks more butt than EDO RAM.

 

[rettahc]

EDO - Extended Data Out.
All DRAM needs to be refreshed to keep the data and programs it stores vaild. The process of refresh creates a big bottleneck in RAM access. So the y created EDO. It was an improvment on FPM DRAM(don't ask its dead, so EDO for that matter) It need to be refreshed much less often so caused less of a bottleneck

 

[NetRyder]

EDO (extended data output) RAM is a type of random access memory (RAM) chip that improves the time to read from memory on faster microprocessors such as the Intel Pentium. EDO RAM was initially optimized for the 66 MHz Pentium. For faster computers, different types of synchronous dynamic RAM (SDRAM) are recommended.

 

[mbunny]

Hehe... i just sold 80 meg of EDO for $90 =P

ahh... gotta love how EDO is worth a fortune lol.

 

[scriptasylum]

Originally posted by rettahc
... FPM DRAM(don't ask its dead, so EDO for that matter) ...

In case anyone's curious: FPM=Fast Page Mode.

 

[Zedric]

The big downside to RDRAM however is that it's very expensive.

 

[Sazar]

Originally posted by Zedric
The big downside to RDRAM however is that it's very expensive.

also has high latencies

concerning the remark netryder had about ddr 266 being twice the speed... its actually a lot more marketing than anything else..

you will be hardpressed to see 2 times the speed difference in tests... though theoretically it is probably something like that

basically instead of having a read or a write every clock cycle (hence single data rate) you are able to do both (hence double data rate)

theoretical advantage not so much in clock speed of the memory but the amount of extra bandwidth afforded...

concerning bandwidth... rdram still kicks the pants off of ddr memory concerning bandwidth.. but with the advent of ddr II (operates like qddr internally) and qdr itself... we should see this move to sdram's favor by next year...

besides... rdram would not work with the current design of amd processors... intel has different length of data path (longer per se in leymans terms) and therefore NEEDS the higher latencies of rdram... but the extra speed and bandwidth help it overcome the drawbacks...

 

[Krux]

Originally posted by Sazar
also has high latencies

concerning the remark netryder had about ddr 266 being twice the speed... its actually a lot more marketing than anything else..

you will be hardpressed to see 2 times the speed difference in tests... though theoretically it is probably something like that

basically instead of having a read or a write every clock cycle (hence single data rate) you are able to do both (hence double data rate)

theoretical advantage not so much in clock speed of the memory but the amount of extra bandwidth afforded...

concerning bandwidth... rdram still kicks the pants off of ddr memory concerning bandwidth.. but with the advent of ddr II (operates like qddr internally) and qdr itself... we should see this move to sdram's favor by next year...

besides... rdram would not work with the current design of amd processors... intel has different length of data path (longer per se in leymans terms) and therefore NEEDS the higher latencies of rdram... but the extra speed and bandwidth help it overcome the drawbacks...

I was hoping some one would say this and of course is sazar :blink:

 

[Krux]

you also have to buy RDRAM in pairs just so you know can't just go out and buy a stick of 128 u have to buy two.

 

[Sazar]

Originally posted by Krux
you also have to buy RDRAM in pairs just so you know can't just go out and buy a stick of 128 u have to buy two.

well yes... but whats that placebo thing called? its like rdram cept all it does is sit in slot and acts like it... so that you don't need a pair..

I can't remember the name... my boss @ work has setup his computer and a coupla other big shots rigs like that...

I setup the socket A and ddr based intel mobo's

not a fan of rdram... too expensive for our needs...

[edit] btw I like your new sig [/edit]

 

[Krux]

thanks first one ive made thats gotten any feed back, my posts reapeared :huh: anyways.....


and I know what your talking about those place holder things but Ive never seen those on sale, only the ram I figured it was an oem thing because Ive seen them in gateways god knows there to cheep to give u two sticks of ram

 

[NetRyder]

Originally posted by Sazar
concerning the remark netryder had about ddr 266 being twice the speed... its actually a lot more marketing than anything else..

I've read that it's all in theory too ... but I was just pointing out that the 266MHz DIMM was called DDR because it's theoretically supposed to be twice as fast as PC133 SDRAM.

 

[JohnnyGreb]

Originally posted by mbunny
Hehe... i just sold 80 meg of EDO for $90 =P

Woot! I got a whole cr@pload of EDO! Me thinks I can find someone to buy it?!?!

 

[Sazar]

Originally posted by NetRyder
I've read that it's all in theory too ... but I was just pointing out that the 266MHz DIMM was called DDR because it's theoretically supposed to be twice as fast as PC133 SDRAM.

but you are disregarding the fact the it is still operating @ 133 mhz hence its not technically any faster now is it? but the read/wrte @ the same time makes it do 2 times as much work.. theoretically...

133 @ double data rate in marketing becomes 266...

thats what I was pointing out....