DDR...... MHZ... PC3200.... PC2100.. HELP?!

Okay... I'm tired of trying to read up and figure this DDR crap out. It's starting to fry my brain. I am so adapted to the basic PC100/133 setups that I just cant seem to comprehend this DDR terminology. Why couldnt they just continue on with the terms... like PC133 is for 133mhz buses and operates at 133... so why didnt they say that since it operates at 266 mhz that it was DDR266.. For example... from what I can understand DDR3200 is the newest fastest DDR available right now @ 400mhz... so why isnt it called DDR400??? Anyways, Im just giving you an overview of why I'm fixing to be so blunt and non-technical-savvy and only talk in megahertz (not PC21"WHATEVER") so you will know what I'm trying to acheieve.

But! I just purchased a Intel p4 2ghz that supports 400mhz, right?... right. So, I figure I'll get me a 512mb stick of the 400mhz (DDR3200) mem to go along. Sounds logical and optimized, right?... right. OKAY, now for the tricky part I DONT understand. I go and research motherboards websites (3 weeks now) and even the new Asus, Biostar, etc that come out and SAY they have the new 533mhz bus support... their DDR specs ask for like DDR2700 and DDR2100 and crap like that! Which are all like 166mhz and 233 mhz! What is the purpose of having a bus speed on the processor and chipset and not being able to use the same bus speed memory? I guess putting it easy as possible - Im trying to look for a motherboard that supports the DDR3200 and will USE it @ 400mhz. Can anyone please explain this memory stuff to me and suggest a good nicely priced mb with 3 slots for DDR not two... I would greatly be in debt to you....

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  1. God help you if you bought a Willamette 2.0Ghz...You need a motherboard that has a DDR chipset, although most only support DDR266/333 for the Pentium 4.

    "When there's a will, there's a way."
  2. Well actually DDR RAM has 2 names one for its speed (MHZ) and one for bandwidth (MB/s). So DDR400=PC3200 because 400 is its working frequency, and 3200 is its bandwidth. So:


    Your P4 2GHz runs at 100MHz FSB Quad-Pumped to 400MHz. Now most 400MHz FSB mobos support the 3:4 CPU:RAM ratio which means your CPU would be running at 100MHz FSB (quad-Pumped), while your RAM would run at 133MHz (Dual-Pumped). The newer 533DSB mobos use the 133MHz FSB, although you can set it otherwise. What you should do is run your proc at a 133MHz FSB, therefore overclocking your CPU to 2.66GHz. I really don't know if there are any chipsets that can run DDR400 at full speed. I mean if you overclocked your FSB enough and used a 4:5 ratio for the CPU:RAM clock, you could get DDR400, but it's rare with your setup. You'd have to run at 160MHz FSB to get 200MHz (dual-pumped) on your RAM. Probably the best you can hope for is to use the 4:5 ratio and a 133MHz FSB to get PC2700/DDR333 performance. Perhaps there are mobos that allow a 2:3 ratio. That way if you ran at 133MHz FSB, your RAM would be at 200MHz (dual-pumped again) so DDR400. I don't personnally know any that acutally support that ratio.

    :smile: Falling down stairs saves time :smile:
  3. Hmmmm.... Didn't think about the Willamette factor... oh well, just ignore the part about overclocking to 2.66GHz then.... :eek:

    :smile: Falling down stairs saves time :smile:
  4. hmm... your post was good but and it was really informative but I think I will have to reread it like 4 times to start to grasp the concept. And BTW, wtf is a willamette?
  5. Yeah, sorry about that. I tried to write it as well as I could, but i guess it was kinda hard to say what I was trying to. Ok good that it helped a bit.

    Does your CPU have 512KB or 256MB or L2 cache? The Willamette has 256KB and performs worse than the Northwood (which has 512KB of L2 cache). Also the NW is built on the .13um process, and can clock a lot higher, whereas the Willamette is slower and already reaches its peak at around 2GHz. We're just saying hopefully you didn't get a Willy.

    :smile: Falling down stairs saves time :smile:
  6. Actually I've got the Visa at hand and am looking through some vendor sites as we speak to buy it. When I said I got a 2 gig pent 4 in my post, I was hypotheticaly speaking... LOL So, when looking for the processor, what is different about them.... I mean I'm sure it wont say Willamette or Norwood, huh?
  7. PC1600 runs at 100mhz (200mhz effective due to double data rate)
    PC2100 = 133
    PC2400 = 150
    PC2700 = 166
    PC3000 = 185
    PC3200 = 200

    and the P4 has a number of different core revisions, which are

    0.18 micron die, 256k cache, "willamette", socket 423, 400FSB
    0.18 micron die, 256k cache, "willamette", socket 478, 400FSB
    0.18 micron die, 128k cache, "willamette" celleron, socket 478, 400FSB
    0.13 micron die, 512k cache, "northwood" A, socket 478, 400FSB
    0.13 micron die, 512k cache, "northwood" B, socket 478, 533FSB

    obviously the one to get is the Northwood.
    its newer, faster, runs cooler on a smaller die size and the low end models, the northwood 1.6A or 1.8A can easily be overclocked to B levels.

    <font color=purple>I am the Motherboard Destroyer!
    Hear Me Roar!</font color=purple> <font color=orange>*SQUEAK*</font color=orange>
  8. can you give also their respective prices?

    <i>if you know you don't know, the way could be more easy ...</i>
  9. LoL

    <i>if you know you don't know, the way could be more easy ...</i>
  10. are you Pumped?

    <i>if you know you don't know, the way could be more easy ...</i>
  11. rofl

    <i>if you know you don't know, the way could be more easy ...</i>
  12. lol no.
    if i did they would be auzzie prices anyway. pretty useless to you.

    <font color=purple>I am the Motherboard Destroyer!
    Hear Me Roar!</font color=purple> <font color=orange>*SQUEAK*</font color=orange>
  13. DDR Memory (Double Data Rate Memory) used especially by AMD processors
    (DDR)266 Mhz (FSB 133Mhz *2) * 8 bytes (64 bits memory bus size) = (PC)2100 (2.1Ghz bandwith)
    (DDR)333 Mhz (FSB 166Mhz *2) * 8 bytes (64 bits memory bus size) = (PC)2700 (2.7Ghz bandwith)
    (DDR)400 Mhz (FSB 200Mhz *2) * 8 bytes (64 bits memory bus size) = (PC)3200 (3.2Ghz bandwith)

    RDRAM Memory (Rambus DRAM Memory) used by Intel processors
    (PC)800 _Mhz (FSB 400Mhz) * 2 bytes (16 bits memory bus size) = RIMM1600 (1.6Ghz bandwith)
    (PC)1066 Mhz (FSB 533Mhz) * 4 bytes (32 bits memory bus size) = RIMM4200 (4.2Ghz bandwith)
    (PC)1200 Mhz (FSB 600Mhz) * 8 bytes (64 bits memory bus size) = RIMM9600 (9.6Ghz bandwith)

    <i>if you know you don't know, the way could be more easy ...</i>
  14. Hey N,

    Not to say that anything that has been posted in this string is wrong..........but I think everyone is answering your direct question, which is about DDR & it's mhz. I think you are not asking the right question(not that I blame you, it is all very confusing). Your first question should be: what mobo's(motherboards) will your flavor of P4(Pentium 4) support? The next question should be: is that mobo a DDR or a RD-Ram(Rambus Ram) mobo. Your last question should be: Which type of ram performs better & how do the prices compare?

    The thing is, all P4's claim to have a 400 or 533 mhz FSB. This is not totally true, the CPU's still runs on a 100 or 133 mhz CPU Bus, the Memory(if you use RD-Ram) runs on a "Quad-Pumped" Memory bus.........so you get 100 mhz(cpu bus) X 4= 400mhz, or if you use RD-Ram 1066mhz & a very good RD-Ram Mobo, you will get 133 cpu bus X 4= 533mhz. RD-Ram is 4X faster than SD-Ram. If you use a DDR(Double Data Rate) mobo it is only 2X faster than SD-Ram. The fastest standardized DDR right now is PC2700/DDR333(166 mhz memory bus X 2= 333mhz). Any other faster DDR that you see online most likely will not out-perform OEM/Stardard PC2700 made by Samsung, by much.

    Back to the big picture: No Mobo supports DDR400/PC3200 yet. All DDR366/PC3000 is just rebadged DDR333/PC2700. RD-Ram needs a RD-Ram Mobo & runs faster than DDR. The CPU Bus is not the Memory Bus, the cpu bus runs at 100mhz or 133mhz, the Memory bus runs at either 4X that if you use a RD-Ram mobo & RD-Ram..........or 2X that if you use DDR. Lastly you need to state in your posts what you plan to use this system for(hardcore gaming, video editting, whatever).

    I would tell you my choice for a mobo, but I haven't gone Intel for quite sometime.........being a cheap guy, I like the idea of a cpu socket type that has some staying power & upgrading when I get the cash.........not like the Intel systems, that the mobo will only take a few flavors of cpus...... Everytime you see a faster P4, you need a whole new mobo to use that chip. Good Luck & keep reading........more of the websites & less in the "Community" to find real info not just second hand info.

    Peace Out...............tile

    god knows your entire system setup & he would answer your questions if he could just stop laughing
  15. but i have an online rates fx (exchange rate server) with realtime rates values. maybe i can use it. an auzzie buck = 0.571 EUR buck this day.
    well but in AUD. there is also the ATS (auzzie schilling) i think but i don't know this currency & its rate.

    <i>if you know you don't know, the way could be more easy ...</i>
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