Help with Ram types, please clear this up for me.!

stealthbig

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Aug 10, 2001
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Well ive become confused with all of the different types of RAM, so please bare with me.. Right now I know there is PC133 and DDR. All I know is that I have 1 PC133 256 mb module in my computer.

I know is that DDR is better than PC133, and there is "PC2700" etc that I have no idea what it is. I think its RDRAM? Anyway I was wondering how all the ram types compare to eachother, I know PC133 is at the bottom of the chain, but would I notice any difference? And what types would me mobo probably handle? Im pretty sure only DDR and Pc133.
"Memory Support
Supports up to 1GB or registered SDRAM
Provides (2) 168-pin DIMM slots
Supports PC-100 & PC-133 memory bus"

And for the future, what wins the DDR or the RDRAM?

Thanks for the help, ive just become really confused with all the ram.. On top of that I think RDRAM has all types of speeds?
 

Ironstone

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Aug 21, 2002
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I'm also searching for answers, but I can tell you a few things until someone smarter comes along!

2700 = 333mhz RAM speed
2100 = 266mhz RAM speed
(both DDR, and better than the old PC133)

There are more boards around using the 2100 ram and apparently Intel are still completing their "validation" process for their chipsets that use 333mhz ram (but you can get "unofficial" boards that can use the Intel 845G chipset with multiplier set to run 333.

There is also Rambus memory (which I think is the RDRAM you see referred to) which is faster but not always apparently worth the money unless you have a specific reason for needing the last word in RAM speed.

In real world use you often don't see an on screen benefits of buying super fast components - or sticking heaps in - unless your apps actually need it. But working out whether they do or not isn't always easy...

There's some articles on this site well worth reading + a FAQ at the top of the RAM forum
 

Ironstone

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If you look through artcles like this one, you'll see that the differences between RAM types and speeds may be quite small - depending on what you are actually doing with it.

It may or may not be worth getting the component that "looks" faster if you don't need it, or it means buying a motherboard, or other total solution that you might not have chosen otherwise, due to price or other compatibility factors.

http://www.tomshardware.com/mainboard/02q3/020722/index.html
 

nja469

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Your board doesn't support DDR or RDRAM, only SDRAM (PC100 or PC133).

Now I'm no memory expert, and I'm sure someone will better explain it (or confuse it) later. This is a crash course, and again i'm not expert. So here we go:

DDR means "double data rate". It is used with newer chipsets instead of SDRAM (like your board) since it runs faster and has more bandwidth. Newer CPU's like the Athlon XP and especially Pentium 4 need much more bandwidth than previous chips.

PC1600, is DDR and it refers to it's bandwidth of 1.6GBPS. PC1600 runs at 100MHz X 2 = 200Mhz DDR. There is PC2100, which has a bandwidth of 2.1GBps and runs at 133MHz x 2 = 266MHz DDR. There is newer PC2700, which can handle 2.7GBps of data and runs at 166 x 2 = 333MHz DDR.

DDR can be used with pentium 4 and athlon systems. Motherboards that use DDR will specifically say so, and will always list the types supported. The Pentium 4 has a memory bus speed of 400Mhz or 533MHz, and athlon xp's run on 266MHz. The faster the DDR, the better the bandwidth between the CPU and memory, which in turn diminishes bottlenecks and increases overall system performance. SDRAM isn't supported on the newest chipsets for the athlon or pentium 4 as its' bandwidth is too low and the type of memory is mostly being fazed out.

RDRAM, or Rambus currently only suppoprts Pentium 4 platforms. Due to royalties and other conditions, it is much more expensive than DDR. I do not know much about Rambus except it currently must be used in pairs, (two 128MB RIMMS = 256MB) and that there is PC800 (3.2GBps) and PC1066 (6.4GBps). PC800 runs at 400MHz x 2 RIMMS = 800MHz, and 1066 is 533MHz x 2 = 1.06GHz. Being that the pentium 4 uses either a 400 or 533MHz front side bus, RDRAM makes most sense in terms of fully exploiting the pentium bandwidth, though it is more expensive and that is why some people use DDR with their pentium 4.

DDR and RDRAM are both evolving technologies, with DDR 400 (PC3200) available soon and a new type of DDR II. Also there are talks of a QDR (quad data rate) technology, and new rambus chips. For more information I'd recommend browsing this article <A HREF="http://www.tomshardware.com/mainboard/02q2/020501/index.html" target="_new">here</A> from Tom's.

Hope I kind of helped, and look below for people filling in on what I know I've missed.



"Opinions are like assholes, everyone has one"
 

stealthbig

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Ok thanks for all the help guys. So im stuck with PC133 until i get something besides the cheapest mobo available. I really needed a new computer and $315 for a new Athlon XP 1800+ is pretty good. I think ill keep my current mobo for a while, and get a real graphics card (integrated now). So basically theres PC133, DDR, and RDRAM.. Thanks for clearing this up for me!