DDR2 400 vs 800

[slaakker]

Howdy,

I recently purchased and built a new computer with a Asus p5w deluxe mobo. This was my first build and had some help picking parts from the salesman at Frys. I spent more on the mobo than I had planned but the salesman said that he could save me some money on the ram.

Now my question. He suggested valuram 400 instead of 800. He said that because it is in a dual channel configuration it would be all I need because it would only run the ram at 400mhz each.

Is this true? Should I have spent the extra cash and got the 800? Is this ram going to bottleneck the speed?

I am running an Intel duo. I think it is the 1.9mhz. I am at work so I can't check it at the moment. The FSB is 800/1600 I think.

Sorry for the newby question. Thanks for any help!

[tkpenalty]

DDR400 doesnt work on DDRII...DDRII is 533,667,800 and 1066... DDR800 > DDR400 anytime of the year, your friend was probably envious and wanted you to have less of a good computer.

[ghost101]

There are also ddr2 400mhz modules (pc2-3200). However, next to no one sells them anymore.

As for what the salesman was saying. The only thing i can assume he meant was that

ddr2 400 RAM in dual channel will have the same bandwidth as ddr2 800 in single channel. However, thats obviously an unfair comparison.

The other thing you should remember is tha ddr2 400 RAM will mean you are running at a divider lower than 1:1 and gives no room for overclocking.

[JC316]

The Fry's guy is either A a retard, or B is trying to scam you. Get the 800, it will DESTROY 400 any ol day of the week.

[Pinchy]

Yeah, he probably meant that 2 channel DDR400 = 1 channel DDR800....but then when you get 2 channel DDR800...

[slaakker]

Wow. Quick replies!

Just so I understand, the current memory configuration will actually slow the performance of the computer because the cpu has to match the memory speed?

I built the computer 5 months ago and it is just not as snappy as I hoped. It runs games like americas army and half life without any problems. It seems to have long load times though. I am about to set up a raid 0 because the hard drive is starting to have errors. Hopefully that will help too.

Thanks for the help! Wonder what I can sell my used ram for on Ebay! LOL

[Pinchy]

When me and my friend (ex_reven) were building our computers, the DDR800 RAM was the last to come in. ex_reven had some corsair 533Mhz RAM and we decided to put it in and see how the computer would run.

We put it in and ran it, and frankly, i wansnt impressed. On a fresh install of XP, it seemed laggy and not "up to scratch". I was actually regretting spending the money on the new comp.

BUT as soon as we got the 800Mhz RAM, things changed. The computer was SO much faster! I really didnt think it would make a difference...but i was wrong, it makes a huge diff.

Id say to sell your RAM and buy new stuff. There is a 2GB pack of G.Skill RAM on newegg for $250 ($30 discount)

[ghost101]

Don't expect miracles from simply getting faster RAM.

[Pinchy]

Not miracles, but definately noticable performance increases.

Like games and stuff wont get that much of a hit...but day-to-day apps will have a faster response time and better performance :)

[ghost101]

http://www.anandtech.com/mb/showdoc.aspx?i=2813&p=6

The impact on gaming is pretty minimal, especially for a 975x board. Other RAM intensive tasks do benefit though.

Basically, agreeing with Pinchy.

[ghost101]

Just so I understand, the current memory configuration will actually slow the performance of the computer because the cpu has to match the memory speed?


Nope, that isnt true. CPU bottleknecking due to RAM bandwidth is pretty much non-existent. This can be proven by using a board which has independent RAM and FSB speeds (eg. 650i boards) and then overclocking the CPU. My earlier remark was about how it will limit overclocking as most boards have the FSB and RAM speeds linked.

[DanTheBanjoman]

It all depends on the CPU you're using. If you run a P4 for example (or even a Celeron) the 400MHz modules will be more than enough. However if you use a CPU with a higher FSB or wish to overclock then faster RAM becomes important. The RAM should at least be able to run at the speed of the CPU's FSB.