ddr2 xx00 pc2 xx00 ?!

From general questions to the harder advanced user topics you will find them here!
Post Reply
iceman600
Legit User
Legit User
Posts: 12
Joined: Sat Dec 29, 2007 4:44 pm

ddr2 xx00 pc2 xx00 ?!

Post by iceman600 » Fri Jan 04, 2008 1:32 am

im building my system right now and im having trouble bout the memory... im reading a lot lately about memory and timings but still cant understand some things with it. like i read about overclocking the memory as you overclock the cpu. it says that you have to make the speed of you memory the same of the speed of the FSB or the prosessor. my problem is i dont know what kind of memory to buy?! there are so many types like ddr2 then followed by numbers then pc2 then numbers again.... what do these number represent? and can you tell me what kind of memory i would buy? thanks... im really am confused about this ram stuff. i wish there is a siple explanation bout this...

hercules71185
Legit Extremist
Legit Extremist
Posts: 847
Joined: Mon Sep 03, 2007 2:47 am

Re: ddr2 xx00 pc2 xx00 ?!

Post by hercules71185 » Fri Jan 04, 2008 2:16 am

if your motherboard supports ddr2 it will say it..
building a system I know there is a more in depth article on it than this. But, till then this will help a little
CPU socket and motherboard socket have to match
motherboard will say the ram it supports. If its ddr2 this is where your numbers are
ddr2533 vs ddr2667 vs ddr2800 . A motherboard that supports ddr2 will support any of these numbers. But, if your motherboard only supports say ddr2 667 then you can only run your ram at 667 even if you buy 800
ddr2 ratings
533 is 4200
667 is 5300
800 is 6400
all they are is the memory speed. 800 is faster than 533 (I know there are technicalities but, this is just to be simple)
So when you are looking at the 2 numbers the ddr2 and pc2 they are linked numbers.

User avatar
DaIceMan
Legit Extremist
Legit Extremist
Posts: 1599
Joined: Tue Jul 18, 2006 10:31 pm
Location: Springfield-ish, Missouri
Contact:

Re: ddr2 xx00 pc2 xx00 ?!

Post by DaIceMan » Fri Jan 04, 2008 7:12 am

what brand and model of motherboard do you have? what processor is it?
Gamer - Thermaltake Element S | PC Power & Cooling Silencer 750 Black | Gigabyte GA-EP45-DS3L | Intel E8400 | Arctic Cooling Freezer 7 Pro | 4GB OCZ Reaper Ram | XFX 8800GTX | Creative X-Fi XtremeGamer | Seagate 7200.10 320GB

HTPC / Folder - Palit 9600GT 1GB Sonic | AMD Phenom 9600 | Corsair DHX 4GB | ECS GF8200A | OCZ StealthXStream 500
Thanks to Palit, AMD, Corsair and ECS for sponsoring the 2008 Folding Give-away!

Image

User avatar
The Black Pumpkin
Legit Extremist
Legit Extremist
Posts: 421
Joined: Wed Mar 29, 2006 11:45 pm
Location: Lake City, Florida

Re: ddr2 xx00 pc2 xx00 ?!

Post by The Black Pumpkin » Fri Jan 04, 2008 7:01 pm

Yes, it is complicated.

Old sdram has the same rating as the fsb clock (66-66, 100-100, 133-133, etc.) because it does things once per clock cycle. DDR has double the rating of the fsb clock (133-266, 166-333, 200-400, etc.), since it does things twice per clock cycle. DDR2 has quadruple the rating of the fsb clock (133-533, 166-667, 200-800, 266-1066, etc.), since it effectively does things four times per clock cycle.

So take whatever processor you want, say the Intel E6420 (which has a bus rating of 1066), and since Intel quad-pumps their cpu fsb, you'd get 1066 ram. If you were getting an AMD cpu, which all use 200 fsb (or HT, but that's another story) you'd get 800 ram, as that has the corresponding bus speed. That's what they mean when they say match the ram speed to the cpu speed.

As far as the PC ratings go (PC 3200 etc. for DDR and PC 6400 etc. for DDR2), it is the estimated bandwidth that the particular speed will provide. In order to come up with it, you take the DDR/DDR2 rating and multiply it by 8. 400x8=3200 and 800x8=6400.

I hope this helps. :supz:
AMD Opteron 1224SE "Santa Ana" = DFI Lanparty UT NF590 SLI-M2R/G
Crucial Ballistix 4x1GB DDR2 800 = Corsair CMPSU-750TX
Sapphire 4870 1GB = Sceptre X20WG-Naga 20" = Logitech X-530 5.1
Seagate 320GB (SATA II) x2 = Samsung SH-S203B (SATA)

iceman600
Legit User
Legit User
Posts: 12
Joined: Sat Dec 29, 2007 4:44 pm

Re: ddr2 xx00 pc2 xx00 ?!

Post by iceman600 » Fri Jan 04, 2008 7:25 pm

i just bought a asus maximus formula SE and it has a FSB of 1600/1333. from what i kno about this is it has a default FSB of 1333 and if i overclock my CPU i can do it up to 1600MHz. am i right?! ( ihave a q6600 as my CPU )

i currently have a xfx nforce 680i LT but im not using it right now cos i have no ram... im still building my system and im still using a laptop for now. im rilly so confused about memory.
if i have to set my system up, what type of memory is better? a ddr2 800 pc6400 or a ddr2 1066 pc8500?

hercules71185
Legit Extremist
Legit Extremist
Posts: 847
Joined: Mon Sep 03, 2007 2:47 am

Re: ddr2 xx00 pc2 xx00 ?!

Post by hercules71185 » Wed Jan 09, 2008 10:43 am

ok, if your motherboard supports ddr2 1066 great its better than 800. You have more options to overclock with. In my honest opinion ram speed doesn't seem to drastically make a difference.. I've tried different settings to get results. ddr2 @ 800 @667 and @ 533

One question I have for some people. Isn't it supposed to be ddr2 666? and ddr2 799.99999999etc

Post Reply