Is is DDR800 memory worth the investment over DDR667 memory?

itgl72

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I was looking at buying this MB:

GIGABYTE GA-965P-DS3 LGA 775 Intel P965 Express ATX Intel Motherboard - Retail
http://www.newegg.com/Product/Product.asp?Item=N82E16819115003

Also going with Intel 6600 CPU and 8800 series VC.

I was looking at getting 2GB worth of DDR667, but the MB can take up to DDR800. Is the investment worth it to go for the DDR800?

I'm not planning on overclocking but want to try and get the most out of the components I am assembling.

I have had great help over in the MB forum, but the more I dig, the more questions I seem to discover.

Its been since 2003 that I built a new gaming PC.

TIA
 

jeff_2087

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If you're not overclocking, then you won't see any difference because they'll both be running at 533MHz anyway, you could even just get DDR2-533. But 667 will at least give you a little overclocking headroom should you change your mind.

So getting DDR2-667 would save you some money, although if you're not on a tight budget you could probably get decent DDR2-800 for not a whole lot more and it'd be a little (little!) faster even at stock speeds because you could tighten down the timings.
 

itgl72

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I guess I always thought that out of the box, stock, 667 was faster memory than 533, and 800 was faster than 667. And I mean, doing nothing but PLUGGING IT IN, and turning on the PC.

I need to read up for the sake of my better understanding.

THANKS FOR REPLYING
 

gallionfc

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If you're not overclocking, then you won't see any difference because they'll both be running at 533MHz anyway, you could even just get DDR2-533.

why will 667mhz and 800mhz ram be running at 533mhz? explain
 

fredgiblet

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If you're not overclocking, then you won't see any difference because they'll both be running at 533MHz anyway, you could even just get DDR2-533.

why will 667mhz and 800mhz ram be running at 533mhz? explain

Because that is what the FSB is running at. The speeds are usually synchronous.
 

shwick

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GALLIONFC i'll give you a quick explanation: Memory runs at the speed of the fsb (front side bus), which is determined by the CPU. The fsb for the E6600 runs at 266 mhz. Since ddr ram is double data ram, you multiply the fsb speed by 2 to get the speed of the ram. 266 mhz x 2 = 533 mhz.

You can make the ram run FASTER without overclocking your cpu- just add a ram divider- 4:5. This is a fsb:ram ratio. A 4:5 means that your ram will run 5/4 = 25% faster than the fsb. So if he DID decide to go with DDR 667 and added a 5:4 memory divider, than he would get full use of his ram without having to overclock, because 1.25 x 266 = 333 mhz ram speed (333 x 2 = 666). I thought motherboards automatically added memory dividers based on the memory speed? I guess they aren't that smart.
 

kukito

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If you're not overclocking, then you won't see any difference because they'll both be running at 533MHz anyway, you could even just get DDR2-533.

why will 667mhz and 800mhz ram be running at 533mhz? explain

The article linked above gives you a better explanation. The memory will run at its rated speed but asynchronously.
 

gallionfc

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If you're not overclocking, then you won't see any difference because they'll both be running at 533MHz anyway, you could even just get DDR2-533.

why will 667mhz and 800mhz ram be running at 533mhz? explain

Because that is what the FSB is running at. The speeds are usually synchronous.

I read the articel at madshrimps, and your right about the synchronous speeds, but it also says that if your using 6400 memory (800mhz) the speeds are just too fast and performance doesnt take a hit like the 5400... I guess its better to go for 6400 ram for future upgrades... ok thanks for the info
 
I read the articel at madshrimps, and your right about the synchronous speeds, but it also says that if your using 6400 memory (800mhz) the speeds are just too fast and performance doesnt take a hit like the 5400... I guess its better to go for 6400 ram for future upgrades... ok thanks for the info
Yeah, I like to think of a runner. At 1:1 (533), the runner has a smooth, synchronous stride. At 5:4 (667), the runner stumbles a little every few steps and is slightly slower because of it. At 3:2 (800), the runner stumbles a bit, but since his legs are moving nearly twice as fast he's quicker overall regardless of the ugly stride.

Keep in mind that if you intend to overclock around FSB 333MHz, then 667 will do fine. Also keep in mind, that nearly all 667 RAM can run at 800 speed just fine. I've had my 667 RAM up to 858MHz before with no problems.
 

itgl72

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GALLIONFC i'll give you a quick explanation: Memory runs at the speed of the fsb (front side bus), which is determined by the CPU. The fsb for the E6600 runs at 266 mhz. Since ddr ram is double data ram, you multiply the fsb speed by 2 to get the speed of the ram. 266 mhz x 2 = 533 mhz.

You can make the ram run FASTER without overclocking your cpu- just add a ram divider- 4:5. This is a fsb:ram ratio. A 4:5 means that your ram will run 5/4 = 25% faster than the fsb. So if he DID decide to go with DDR 667 and added a 5:4 memory divider, than he would get full use of his ram without having to overclock, because 1.25 x 266 = 333 mhz ram speed (333 x 2 = 666). I thought motherboards automatically added memory dividers based on the memory speed? I guess they aren't that smart.


So you think I can save a few dollars and skip the ddr800, go with ddr667 and then add a ram divider- 4:5?

I have never done this, is it hard to do? Will I burn anything out quicker? Will this be ok on the GIGABYTE GA-965P-DS3 MB I was planning on?

I would love to learn more about this stuff- Thanks for the article!
 

kukito

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So you think I can save a few dollars and skip the ddr800, go with ddr667 and then add a ram divider- 4:5?

I have never done this, is it hard to do? Will I burn anything out quicker? Will this be ok on the GIGABYTE GA-965P-DS3 MB I was planning on?

I would love to learn more about this stuff- Thanks for the article!

If you go with 667 then I'd suggest you manually change it to 533 and run it synchronized to the FSB. Then you can experiment with overclocking using wusy's guide. If you follow the guide carefully you will learn a lot more. 8)
 

shwick

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kukito, do you think running the 667 mhz ram at 533 mhz synchronously with the fsb would provide more performance than running it asynchronously with a 4:5 divider (667 mhz)?
 

kukito

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kukito, do you think running the 667 mhz ram at 533 mhz synchronously with the fsb would provide more performance than running it asynchronously with a 4:5 divider (667 mhz)?

According to the article linked above, yeah. From personal experience I couldn't tell the difference. I still run it synchronously because it allows me to overclock my E6600 up to 3 GHz without messing with the timings. You can also tighten the timings if you don't overclock. Even though I only oveclocked just for the sake of it and then reverted back to the stock 2.4 GHz (because of the noise), if I ever need a boost in the future I can just get a better cooler (or put up with the noise).
 

sunangel

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Are you kidding? DDR2-800 blows a hole in DDR2-667. Forget what people say about timings. Bandwidth is the key. You move more (data) per load, instead of moving less more often.

I guess I should also comment that the FSB isn't the only lane that is using the memory. If your using a G965 board, the X3000 is going to use some of that bandwidth. If your downloading a file from the internet or across a lan, it will be stored in memory temporarily until it is completely downloaded and transferred to the hard drive. If your transferring data between hard drives, some of the memory's bandwidth will be used for cacheing the files. As you can see, the FSB is not the only component using the memory at the same. Again, I reiterate, bandwidth is more important than timings.