Sorry your browser is not supported!

You are using an outdated browser that does not support modern web technologies, in order to use this site please update to a new browser.

Browsers supported include Chrome, FireFox, Safari, Opera, Internet Explorer 10+ or Microsoft Edge.

Geek Culture / DDR2 Questions...

Author
Message
Sid Sinister
19
Years of Service
User Offline
Joined: 10th Jul 2005
Location:
Posted: 5th Dec 2006 22:18 Edited at: 5th Dec 2006 22:20
Link
I know there's been so many reviews and tests and the like about my questions, and I've read them, but I'm still not seeing the light there. So thats why I came to you guys (Don't you feel special, just a little? ). *cough* anyway.

First lets get the specs out of the way.

Motherboard:
ABIT AW9D-MAX Socket T (LGA 775) Intel 975X ATX Intel Motherboard

Processor:
Intel Core 2 Duo 1.86Ghz

Hard Drive:
Western Digital Caviar RE WD1600YS 160GB 7200 RPM 16MB Cache SATA 3.0Gb/s Hard Drive

Video Card:
SAPPHIRE 100186L Radeon X1950XT 256MB 256-bit GDDR3 VIVO PCI Express x16 HDCP Video Card

Power Supply:
Rosewill RP550V2-D-SL 550W SLI Ready-ATX 12V V2.01 Power Supply

RAM: ?

There lies my question. The AW9D can take 533/667/800 DDR2 RAM. I know that timings sync up better with 533 (something to do with the FSB) and that 667 with lower clocks can preform better than 800 with medium clocks. So what should I get? Does 533 perform best of them all because it's 1:2 with the FSB? Or does DDR2 667 work best? What about 800? And could someone explain to me whats DDR2 675 is too? I heard it's better for overclocking, which I plan on doing a bit off. So if I go with 667 should I choose 675 instead?

Thanks guys, I appreciate it.

Back to top
Profile PM Email
Kenjar
19
Years of Service
User Offline
Joined: 17th Jun 2005
Location: TGC
Posted: 5th Dec 2006 22:31
Link
To be honest I've always taken it on faith that PC2-6400 was the best because it runs at 800Mhz, ceratinly DDR2 and DDR3 has been used in graphics cards for a while now, I don't think the bus speed affects it that much, it's either able to send data at full rate or it isn't.

Basically, if you have the cash, it's prob best to get the fastest type you can and plug it in. From reading that motherboard link you sent, it looks a little bad. If you are purchasing a new MB, perhaps the MSI AM2 570 would be a better model to go for, I've read nothing but good reviews about it.


http://blog.darkbasichelp.co.uk
Back to top
Profile PM Email Website
Sid Sinister
19
Years of Service
User Offline
Joined: 10th Jul 2005
Location:
Posted: 5th Dec 2006 22:40
Link
Ew, thats AMD! Remember the Core 2 Duo's run on a LGA775 socket, hence I would need a LGA775 socket board. I don't feel like paying more money for the same amount of speed. Intel Core 2 Duo's beat the crap out of the X2's every time. Thats why I want to stick with intel this time around.

But I'm all ears, how is the AW9D board bad? I was looking at the MSI Platinum but this one was a bit cheaper.
Back to top
Profile PM Email
Kenjar
19
Years of Service
User Offline
Joined: 17th Jun 2005
Location: TGC
Posted: 5th Dec 2006 22:50
Link
If you go to that link you posted, and read the comments on the side, you'll see.

Quote: "Bizarre LEDs, max DDR2 667 speeds with Corsair pc6400, kentsfield causes CMOS errors even with up to date BIOS.., cruddy 1st party software monitor."



http://blog.darkbasichelp.co.uk
Back to top
Profile PM Email Website
Sid Sinister
19
Years of Service
User Offline
Joined: 10th Jul 2005
Location:
Posted: 5th Dec 2006 23:03 Edited at: 5th Dec 2006 23:03
Link
Yea I see it, but thats just one bad experience out of many who reviewed. Thats like not eating ice cream again after you dropped your cone once... lol

I've never done this before. Should I listen to a couple bad reviews when they're are plenty of good ones?
Back to top
Profile PM Email
Kenjar
19
Years of Service
User Offline
Joined: 17th Jun 2005
Location: TGC
Posted: 6th Dec 2006 00:13
Link
I must admit that I tend to listen to the bad reviews more than the good, because alot of people post too quickly after getting the item.


http://blog.darkbasichelp.co.uk
Back to top
Profile PM Email Website
Sid Sinister
19
Years of Service
User Offline
Joined: 10th Jul 2005
Location:
Posted: 6th Dec 2006 01:41
Link
Ok so we've talked about the motherboard. I'm looking for advice on the RAM.

Come on guys!
Back to top
Profile PM Email
Raven
19
Years of Service
User Offline
Joined: 23rd Mar 2005
Location: Hertfordshire, England
Posted: 6th Dec 2006 02:43
Link
Ram that uses a bigger CL value will out-perform that running at a quicker overall speed.

To break it down basically RAM has several performance attributes that are noted.

Main one is SDR/DDRx
Single Data Rate and Double Data Rate are the multipliers for the amount of data capable of being processed.

For example: 100MHz RAM
SDR = 100MHz - 800MB/Second
DDR = 200MHz - 1.6GB/Second

DDR2 and DDR3 are additional syncronised data lines.

DDR2 = 400MHz - 3.2GB/Second
DDR3 = 800MHz - 6.4GB/Second

While the overall data throughput is expanded, something to note about them is that this is due to a wider data address.
DDR (2bit), DDR2 (4bit), DDR3 (8bit); So it's capable of copying bigger amounts of data I/O.

This said this isn't the *only* factor in RAM performance.
Those numbers after the Ram that are 1-1-1-1, ever wondered what they mean?

In order: CAS-RCD-RP-RAS

CAS - Column Address Strobe (more commonly known as CL, Clock Latency), this is the time in which the ram takes to access a column of data (i.e. 64k chunk)

RCD - Row address to Column address Delay, this is basically the latency between getting data location and accessing it.

RP - Row Precharge time, this is the amount of time it takes between operations to close and open requests.

RAS - Row Address Strobe, the amount of time it takes to access after a data request.

All of the above are measured in clock cycles. So obviously if you have a 200MHz 1-1-1-1 RAM and 100MHz 1-1-1-1 RAM; then the 200MHz will outperform the 100MHz by theoretically 2x performance.

This said, 200MHz 2-2-2-2 against 100MHz 1-1-1-1 RAM and suddenly the result become very different, and the overall performance ends up being nearly identical.

Most important of all of the values are the CAS(CL) and RAS(ATP), as these are the main access speeds; that determin how long the data being send is accessed and stored. The smaller these values are the better.

DDR3 800MHz 5-3-3-6 might look good, but against DDR2 533MHz 3-2-3-4 you're looking at the 800MHz one being quite a bit slower on the whole.

Hopefully this should help you find a RAM that will suit you're system best. While I agree more throughput, and core speed is good; on the whole there's no point in buying a Ferrari when you're forced to drive it at 70MPH.

Intel Core 2 Duo E6400, 512MB DDR2 667MHz, ATi Radeon X1900 XT 256MB PCI-E, Windows Vista Business / XP Professional SP2
Back to top
Profile PM Email Website
Sid Sinister
19
Years of Service
User Offline
Joined: 10th Jul 2005
Location:
Posted: 6th Dec 2006 03:40
Link
WOW Raven, thanks, you that helped alot. I've been looking on newegg lately but alot of the 533 and some of the 667 memory seems ancient. I'm trying to get some good quality, low latency 533 ones now.

So then let me get this straight. DDR2 533 rated at 3-3-3-10 would run faster than DDR2 800 4-4-4-12?
Back to top
Profile PM Email
Raven
19
Years of Service
User Offline
Joined: 23rd Mar 2005
Location: Hertfordshire, England
Posted: 6th Dec 2006 04:00
Link
Yeah, you'll see quite a visible performance difference between the two as well.

Intel Core 2 Duo E6400, 512MB DDR2 667MHz, ATi Radeon X1900 XT 256MB PCI-E, Windows Vista Business / XP Professional SP2
Back to top
Profile PM Email Website
Sid Sinister
19
Years of Service
User Offline
Joined: 10th Jul 2005
Location:
Posted: 6th Dec 2006 04:56
Link
amazing...

how about 667 with the same clocks (or near it) vs. DDR2 800 at 4-4-4-12? Would that be better? Or would it be worse/the same because it's not 1:2 with the fsb?
Back to top
Profile PM Email
Raven
19
Years of Service
User Offline
Joined: 23rd Mar 2005
Location: Hertfordshire, England
Posted: 6th Dec 2006 05:31
Link
well if you want "perfect" compatibility where the FSB and RAM match speed, then you will need to use the on-board overclocking tools to change the CPU from 266MHz 6.9x to 333MHz 5.5x

this said, the FSB doesn't matter much conserning 533MHz and 667MHz; in-fact all the 667MHz will allow is more data bandwidth, you won't actually see much (if any) performance increase. It also will be perfectly compatible with the CPU with no issues of bottlenecking.

on the other hand using 400MHz (DDR2 800) would cause some very annoying compatiblity as it will bottleneck the performance of your processor. might sound weird because overall it can handle more but it's down to the FSB here.

266MHz is a multiple of 3
400MHz is a multiple of 2

as such they would not be synced by the system as the processor will be running far slower than the ram would just end up not being used fully; then it would be also waiting the CL4 for each update on-top of this meaning that you can end up with quite a performance gap.

The only way to combat that would be to alter your FSB to a multiple of 2... for example 280MHz forcing the CPU to run either slightly quicker or slower than originally intended (provided you have access to change the multiplier otherwise it'll be faster)

Also given the CPU wasn't design to run at such a multiplier it can cause the board itself to crash or despite running at a quicker speed actually end up having to wait to read from the memory buffer to cache. Slowing things down further between CPU and Mobo, as well as CPU and RAM.

Long and short... 533MHz RAM is probably the best choice for your motherboard and will give you the best overall performance. Just try to find one with the lowest CAS-RAS and you're pretty much set.



Intel Core 2 Duo E6400, 512MB DDR2 667MHz, ATi Radeon X1900 XT 256MB PCI-E, Windows Vista Business / XP Professional SP2
Back to top
Profile PM Email Website
Sid Sinister
19
Years of Service
User Offline
Joined: 10th Jul 2005
Location:
Posted: 6th Dec 2006 05:40 Edited at: 6th Dec 2006 05:47
Link
Ok, wow, thanks Raven for all your help. +15 points for you. You should write an article or something because that was seriously the most understandable thing I've read on the topic thus far. Thanks for all your help mate. Looks like I've got some shopping to do!

EDIT: Just one more quick question though. They're are two DDR2 533Mhz the PC2 4200 and the PC2 4300. Whats with that?
Back to top
Profile PM Email
Raven
19
Years of Service
User Offline
Joined: 23rd Mar 2005
Location: Hertfordshire, England
Posted: 6th Dec 2006 05:57
Link
PCx-xxxx is the Bandwidth Performance

i.e.

DDR 100MHz PC-1600 would mean it has 1.6GB/second Bandwidth

there is a simple sum to calculate this:

#constant SDR = 1
#constant DDR = 2
#constant DDR2 = DDR * 2
#constant DDR3 = DDR2 * 2

#constant BitRate = 8 // this is always 8, as 8bit = 1byte

global DataRate as dword = SDR // Ram Type
global DataSpeed as dword = 100 // MHz
global Bandwidth as dword // Bandwidth output

Bandwidth = DataSpeed * DataRate * BitRate

text 0, 0, str$(Bandwidth) + "GB/second"

not sure how one ram could be quicker than another, unless they slightly enhanced the speed and multiplyer, so rather than 100MHz x2 it's probably 110MHz x1.8 or something.

Intel Core 2 Duo E6400, 512MB DDR2 667MHz, ATi Radeon X1900 XT 256MB PCI-E, Windows Vista Business / XP Professional SP2
Back to top
Profile PM Email Website
Back to top

Login to post a reply

Server time is: 2024-11-17 23:25:44
Your offset time is: 2024-11-17 23:25:44