AM2 MoBo / DDR2 RAM compatability question

Rand0m7158

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I plan on getting an AM2 sytem pretty much solely used for gaming and I've chosen the ASUS M2N-SLI Deluxe ATX for my motherboard. It says that the DDR2 standard is DDR2 800, but can I use anything less than 800 (667 PC2 5400?) and it still be compatible?

Thanks
 

sailer

Splendid
As long as its DDR2 memory, you should be able to use a lessor number memory, but you won't get the performance. Kind of like having a V-8 engine in your car and pulling out a few spark plugs. It may work, but it won't work well. And no, I wouldn't recommend it.
 

kais

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should work perfectly fine, i used ddr2 400 on my 975x which only supports 533 and 667, ive also used higher so it doesnt matter what speeds they are but just as long as its ddr/ddr2 :D
 

sailer

Splendid
Like you say, and I said before, it should work. As long as its DDR2 memory going in a DDR2 motherboard. The differences of 400, 533, 667 etc will effect total performance. How big the difference is will vary according to the overall system, but generally, the better the memory, the faster the machine.
 

1Tanker

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Like you say, and I said before, it should work. As long as its DDR2 memory going in a DDR2 motherboard. The differences of 400, 533, 667 etc will effect total performance. How big the difference is will vary according to the overall system, but generally, the better the memory, the faster the machine.
This is true but, i wouldn't suggest going below PC5400(667) as AM2 is very dependant on either high-speed(800>)or tight timings(3-3-3-8 ). Many reviews have shown that for an AM2 to perform at the same levels as a s939 system with 2-2-2-x @ 400, you'll need 667(3-3-3-8 ) or 800 (4-4-4-12). GL :)
 

sailer

Splendid
I agree. I wouldn't go below PC5400 (667) myself. Otherwise, its like shooting yourself in the foot and still expecting a quick time in the 50 yard dash. The original queston was whether or not a lesser memory could be used. Though it could, it wouldn't be good.
 

lordroddington

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how about on an am2 sempron system? would ddr2 800 be as important since the processor is slower anyways? if i was building an am2 sempron system i wouldn't want to have to pay a lot for ram if ddr2 667 was enough
 

sailer

Splendid
Try looking at it this way. Your computer wants DDR2 800. Yes it costs a bit more, but it will be even more expensive if you buy DDR2 667 now and then buy DDR2 800 later. A sempron chip may be more sensitive to the lessor memory, maybe not. I don't know. As to my first attempt of analogy, it would be like buying a V-8 in your car and then only putting in 6 spark plugs. You won't get the speed that your computer is able to provide when using the lessor memory.
 

dg6464

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Sorry, came late in on this one. I sell computer products, and build them. The first AM2 system we built was an ASUS board. Make sure that you strictly follow the manufacturers of RAM listed in the manual. The motherboard we used would only boot correctly using Micron 667MHz RAM, no other type of 667MHz DDR2 would work. The board states it was 667MHz compatible... but of course we all know this can be a lie. Also, all other RAM we tried worked (pertaining to your question, yes the lower speed RAM worked fine with all brands except OCZ). The weird thing about this motherboard was that it would not boot up with ANY speed or variation of OCZ RAM, so if your thinking high-performance RAM i would not suggest OCZ for socket AM2 yet, until they have aged a bit, or have some BIOS revisions that will fix the issues. All in all, the experience I had with the AM2 system was fine, except the finding of a compatible memory brand, other than that if we would have checked the manual first (RTFM), we would have been fine. Once the products have aged a bit, and we get some BIOS flashes ect.. I think the RAM issues will go away. The board we used was extremely fast, and all-in-all I liked it... The main reason I liked this board was that once we got compatible RAM installed, the system on startup just blows any older style boards out of the water. Within 2 seconds of pressing the power button, the system had already tested RAM, found all the drives, and had checked all of the drivers for bootable devices. Even after adding more SATA drives ect.. it still flew on startup. Anywayz sorry to go off topic with AM2, but that is my rant/ two cents.

Summary: Yes the boards will work with slower-speed DDR2 than 800MHz, but make sure u get a compatible brand (not OCZ), but if you can afford it, and have the patience, the system will work to it's full potential if you use 800MHz DDR2, of a compatible brand.

:twisted:
 

yourmothersanastronaut

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I bought 2 GB of Corsair XMS CAS4 (EPP supported) for my AM2 Athlon 64 X2 build this week (specs in the siggy) - it should be here monday or tuesday, and I'm not expecting any problems.

The RAM will work as long as the number of pins (in AM2's case, DDR2 has 240 of them) is the same. The RAM speed is pretty much irrelevant as far as compatibility goes. If the RAM physically fits, the motherboard can supply the necessary voltage, and the motherboard maker says the RAM will work (Asus and Corsair generally play nicely together), it will work.
 

hella-d

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Yes You Can Use Any DDR2 However Id Reccomend Usig The Fastest That You Can Afford (2GB If Possible) Bacuase The Current Generation Of AM2 CPU's Work Best With Faster DDR2 Grades
 

shadox

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I just built that system. If you go to the mobo website and download the qvi you will see the "approved" lists....this is crap. Not that these are bad...but they are not the best ones and is very limited. I got gskill..THEY DON'T WORK...unless you send back to manufacturer (which they will pay for). The corsair xms2 works. Use there ram guide at asus over the avi... they say it is up to date. In the qvi they do suggest several slower speeds of ram that you can use. Remember to read the newegg posts to see if something else has come up in the last week.
 

sailer

Splendid
That is part of the problem for sure, motherboard manufacturors. I read of someone today that bought a Gigabyte board that wasn't responding to the recommended ram (DDR2 800) and he was told to go down to DDR2 533. The board is advertized to use the 800, so why doesn't it work with 800? It would sure make it easier on customers if the products worked as advertized. So DDR2 533 or 667 is compatible, it just isn't the best for speed, nor does it match the advertized spec.
 

yourmothersanastronaut

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As I posted before, a BIOS update should fix that. Just search for the latest BIOS revision for that board, download it, and flash it up. All RAM issues should clear up if Gigabyte got it right.
 

MrsD

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how about on an am2 sempron system? would ddr2 800 be as important since the processor is slower anyways? if i was building an am2 sempron system i wouldn't want to have to pay a lot for ram if ddr2 667 was enough

Yes DDR2-667 is fine for sempron, however when you upgrade to a new 65nm X2 down the road do you want to buy new ram again??
Probably not. I'd recommend DDR2-800 with low latency. The lowest you can afford, no more than Cas4.

The board is advertized to use the 800, so why doesn't it work with 800?

Did you manually set the DDR2 voltage in the bios? I had the same problem with my MSI board. The mobo defaulted to 1.8v which was fine for 667 but I had to bump it to 2.1v to match my OCZ 800 or it didnt have enough juice to fire up. Many people are having this problem and dont realize you have to manually change it, people assume, as I did, that the mobo will auto detect. Secondly the SPD timing problem should be worked out by now, if you get memory sticks that wont boot up they are probably old stock. As for a bios update, that had no bearing on the problem with my MSI.
 

Fagaru

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yes it is, when it says its ddr2800 it means it can go up to ddr2800, and if ur a guy that doesnt upgrade cpu or anything liek that i suggest 939 because its better at the moment and all the types of ram isnt confusing. am2 right now sucks, 939 is superior.
 

1Tanker

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how about on an am2 sempron system? would ddr2 800 be as important since the processor is slower anyways? if i was building an am2 sempron system i wouldn't want to have to pay a lot for ram if ddr2 667 was enough
Speed should matter on Sempron also, but keep in mind AMD states that sAM2 A64,FX,and x2 IMC is DDR800 compatable, yet they say that sAM2 Sempron's IMC is only DDR667 compatable. I'm not sure why the difference, but is worth keeping in mind. :?