Question about Ram

[BioAlien]

Hey, not long ago (like 2 week) i posted a tread here, for a question with a motherboard i wanted to buy, and it look like it was deleted...

so i want to know if 400mhz memory will work on my computer, because right now i use 333mhz one.. and i read something about my system that my prossesor is 333mhz or something like that.. so do i need a 400mhz prossesor for ram with 400mhz?
my prossesor(dont look like that though..)
http://www.compuvest.com/Description.jsp?iid=183028
see its writing 333mhz

but do i need a 400mhz one? like this one
http://www.compuvest.com/Description.jsp?iid=183124

for 400mhz ram to work?

[Assassin]

yes, i believe you do.

[BioAlien]

do what? have to buy a new prossesor for 400mhz memory to work?

[darkshadow]

no you wont, in MOST cases higher speed ram will work just fine, it will just work at the lower speed, so even if you do buy ddr400 while your fsb is 333, the ram will just run at ddr333, so it should be fine, it actually better to do so if you plan to overclock you fsb, dont buy ddr2 ram however (533), if your mobo doesnt support ddr2, it wont work

[Deadfire]

no you wont, in MOST cases higher speed ram will work just fine, it will just work at the lower speed, so even if you do buy ddr400 while your fsb is 333, the ram will just run at ddr333, so it should be fine, it actually better to do so if you plan to overclock you fsb, dont buy ddr2 ram however (533), if your mobo doesnt support ddr2, it wont work

Props to Dark on this one.

Yep your memory will dial down to the motherboards specs and of course despite the similar names DDR and DDR2 are NOT interchangeable and are NOT compatible with each other. I may want to note that DDR2-3200 (400) does exist so don't confuse the two.

Dark did talk about over-clocking and memory. Aside from the PC Rating on ram there is also another number or factor thats important to note. This is the Memory CAS latency which refers to the number of clock cycles needed to access the memory. Most mermory will have a rating of at least 2.5 or 3.How you find it when your shopping is in the numbers listed after the model number for a stick. The first number is the CAS of it.

Other things you can do to add the extra punch is changing the settings for memory timings in the BIOS but I'll explain that when it's needed

[BioAlien]

with my current motherboard i can't overcloak, but with my new one (i will have it tommorow) i hope i will be able to, so i can overcloak my fsb to 400mhz, so if i overcloak it, my memory 400mhz will work at normal speed?

[darkshadow]

err overclocking from 333 to 400mhz is almost impossible, thats a 67mhz gain, thats like 134 mhz extra on you fsb! doing that would need some serious proffessional tools, my fsb is pumped up 100mhz extra, and i simply can not go further without some proffesional cooling and stuff

however, if your new mobo already runs at 400 mhz, you wouldnt need to overclock + i can see your old ram ( 333) struggling badly to reach 400mhz, see if your new mobo supports 400mhz

[Deadfire]

Well this is the hard facts PC3200 (400mHz) 400 is it's Effective Clock speed, although it's actual is half that at 200.


however, if your new mobo already runs at 400 mhz, you wouldnt need to overclock + i can see your old ram ( 333) struggling badly to reach 400mhz, see if your new mobo supports 400mhz

It's more of the Chipset then the mother board (I'm thinking thats what your refering to anyway)

EDIT: well after going to your links (Duh!...I'm a idiot) your processer has to match your Chipset. because your processer is a 2800+ it's a 333Mhz chipset. So we are going back to my first answer

It's 333Mhz your going to use PC3200 or PC2700 end of story.

[complich8]

Yikes ...

Err, just so you know, on most modern motherboards, I'm pretty sure the ram is capable of running asynchronously with the system bus.

Which means that you can have a 400 mhz fsb and 333 mhz ram, or vice versa.

In fact, my slightly aged P4 has an effective 800mhz fsb (quad-pumped 200mhz) and ddr-400 ram, but my roommate's even older p4 has a an effective 533fsb and still uses ddr-400. Further, the AMD64 lines have 1ghz fsb speeds, and ALSO use DDR400.

Even further back, my old thunderbird's board was capable of running it at 133fsb, or 100fsb, and capable of independently adding up to 33 mhz to the system bus speed to drive ram (so with a 133-fsb athlon, you could run the memory at 166mhz, if you could find the modules to drive that high).

In other words, these things don't have to match. It's nice when they do (makes access and scheduling a little easier), but they don't have to. You should be more concerned with what your motherboard supports ... but in general DDR-400 is backwards-compatible with earlier generations -- effectively, it's just higher quality versions of slower memory, rated for higher clock speeds.

I'd more recommend looking up your motherboard on crucial.com's memory selector, and seeing what it's compatible with. Go from there.

[BioAlien]

i went on crucial.com, but.. i can't seems to find my motherboard..
http://www.msicomputer.com/product/p_spec.asp?model=K7N2_Delta2-LSR&class=mb

even in the search panel... i can't find it...

unless someone tell me that even with 400mhz ram, my cpu will work just fine... i will stick with the 333mhz one...

[darkshadow]

i think we already told you that numerous times >_>

[complich8]

from the board's site that you linked:

• Support Dual channel PC3200/2700/2100/1600 DDR SDRAMs
• Supports both 64-bit and 128-bit DDR SDRAM
• Maximum memory size of 3GB
• Supports 2.5v DDR SDRAM DIMM

So yes, PC3200 = DDR400 = supported. When you order, you should order a pair, and operate them in dual-channel mode (which makes things substantially faster).

[BioAlien]

alright... so even with my fsb 333mhz prossesor, i can use PC3200?
also.. do i realy need dual channel memory, or it work with normal memory?

[complich8]

"dual channel" is a memory operation mode. It takes two ordinary dimms (that are identical size, timings, and preferably are just completely identical) and runs them in parallel. It's sort of like RAID-0 for memory.

Even if the memory clock is faster than the cpu bus speed, memory is still often a bottleneck, because of latency.

If you want to run in dual channel mode (which you probably do), you'd buy your memory modules in pairs, and put them in in pairs (following the instruction manual's directions on where to put those pairs), and life would be good.

In many cases, you don't strictly have to do that, but you won't get dual channel's benefits if you don't. Not using dual-channel when you've got it and got the modules to use it is like cutting off your left nut simply because you've got a right one too.

[BioAlien]

well.. now i got my new motherboard (using my old 333mhz ram) and it work fine (just had to waste 1hour before internet work again -.-") sadly the case i ordered with my motherboard (cooler master centurion 531) is not working... so have to send it back...

so i will think about it (about the ram) and buy those that cost less, and have over 512ram