I'm building a new system, and finding specs for memory (DDR) confusing. I already know I'll be getting a P4 2.4ghz with 400/533 socket mhz. But I'm noticing that memory specs also have speed ratings .... with the price varying greatly. Is it really necessary that the memory speed match the bus speed? It would mean the difference between an $80 512mg DDR vs. a $200 512mg DDR.

Thanks much!

Hi DarkDrive

If I remember correctly the 400/533 simply equates to 2 front side bus speeds

400=100

533=133

A DDR 266/333 or PC2100/PC2700 module should be fine.

A DDR 266 for the 100 quad pumped bus (400)

A DDR 333 for the 133 quad pumped bus (533)

You definately shouldnt have a situation were the bus speed far exceeds the memory rating.

Memory speed really depends upon your applications, and just how cutting-edge you want to be. The fastest memory right now is Kingston's HyperX DDR 500MHz (PC4000) Memory Modules, which aren't 533Mhz anyway. It is absolutely not necessary to match memory speed to cpu bus speed.

The new boards with 533Mhz FSB will run different memory speeds - from 133Mhz up. Which board will you use? I have an Asus P4PE which will run DDR memory up to DDR400 (PC 3200). I am currently using 2 512MB DDR 333 memory sticks.

Use http://www.pricewatch.com/ to search for memory. Stick to one of the main brands, such as Crucial, Micron or Kingston and you won't have memory problems. Just looking briefly, you can get 256MB of Micron DDR333 for $38, or 512MB Kingston DDR333 for $78.

It really depends upon what you'll be doing with your system. Post more about the software you use, and the motherboard, video card, and hard drive.

I build and repair computers, and where I live in China, they think Kingston is the best. It really doesn't matter if you get one of those that I mentioned. I have never had a problem with any memory by those manufacturers. They are all CL 2.5 and non-ECC. If you don't understand cass latency and error correction control, we don't need to discuss those figures :-)

Post back your board, video card (onboard or pci/agp card), hard drive and applications.

More details:

I'm building from the ground up (all new) ....

Shuttle SB51G barebone with Intel 845ge and ICH4 chipset.
P4 2.4ghz, 512 cache, 533mhz bus
120 gig HD
DVD/CD RW
512 mem
17" LCD
And Mandrake 9.1 on the way

I should be able to get all this for $1150.

What will I use it for? Well, I'm not much into gaming, so the typical surfing, email and such. But I hate slow machines! Eventually I may look into making this a video machine ..... putting a TV card into it, watching movies, etc.. (it has an AGP slot).

If it were me...
http://www.crucial.com/store/PartSpe...64Z335&cat=RAM

I've got 512 of crucial in my box and never had a problem with the memory.

Blinker_Fluid's memory selection is great - although you could save about $12 with the Kingston - they have the same specs and same lifetime warranty.

I've been looking at that XPC, and wondering why you are buying it, versus a regular miniATX or something else? It looks really cute, but the price is a bit steep for what you're getting.

You can install DDR 200/266/333 * 2 modules of each. For your current applications your system would be fast enough with 128MB of DDR333, but I would suggest using 512MB since you may want to upgrade in the future, and you can only install 2 slots - and for the video apps you'll definitely want to go to 1GB.

That onboard video will take some of your memory, too. Altough I couldn't find how much from Shuttle's site. Won't matter when you add an AGP card.

Another consideration is that you can only use ATA 100 hard drives, versus the new ATA 133's or a SATA 150. You'll want hard drive speed for video work. A raid controller would allow you to stripe 2 hd's and get some speed, which this board doesn't have, either. And with only one PCI slot, you don't have much that you can add. Would you network this computer with another? If so, you need a hub or router or 2 nic's. Just some thoughts for *down the road*.

Hey, buy a good stick of 512MB DDR333 (PC 2700) and you'll be pleased with your memory purchase.