upgrading RAM

Hi!

I'm rather fed up with the low amount amount of memory my computer has installed (only 512MB), and I want to upgrade it a bit. So, I have read the user guide supplied with my motherboard (Asus A7V600) and found out that I should get DDR-DIMM RAM. There are three slots for RAM bricks on the motherboard, but the user manual says something like: "PC3200 maximum to 2 DIMMs support only". What does that mean? I was planning to buy two more 512MB RAM bricks (that totals in 1536MB RAM when we take in account the brick that is already installed), but will that be possible considering this warning? What does the "PC3200" label mean anyway?

And: what other parameters should I look at when I upgrade RAM? (I just don't want to end up with two extra bricks that don't work)

Thanks a lot!

PC3200 has to do with the bus speed. Most times you can get a faster speed chip and the mobo will use it only at the design speed. So if you got a PC4400 your mobo will use it at 3200. Other than that just make sure the 1.5GB you want is within the maximum capacity your mobo supports.

Here is a mini Ram tute:

Firstly: Ram is like every other part of your system. Some will tell you you need to pay the most and get the highest end no matter what, or a certain brand is all you should ever use. This is a load of huey, just like Intels or AMDs are better in every case, no matter how you use it. It is an outright lie. Usage is everything. Speed and Size need to be taken into account for that, if you get too fast of ram, it will just throttle back anyways. But it may be better to get more of a slower speed if you do massive multitasking but no encoding or gaming, because you are using more ram, not faster speeds to do what you do.

Basic: Type: PC-100, PC-133 are basic, used on older systems. Then comes rdram or rambus, which comes in a range of speeds, and DDR(and DDR2, DDR3, and DDR4) those come in speeds ranging from 2100, 2700, 3200, 3500 and higher(which are not really fully supported yet. based on their speed...unless you are overclocking, but let's not get into that) 2100 means 266Mhz of speed, which is double "normal ram" or 133... hence Double Data Rate(DDR). 2700 means 333Mhz, 3200 means 400Mhz... etc.

1) Size. How much do you want? That can be 128, 256, 512mb, or 1gig per stick. Depending on your chipset on the mobo, you may have a maximum amount, for instance, 2gig or 4gig total.

2) Sides: Ram comes in single sided and double sided. 1gigs still currently only come in double, many 256s and 512s come in either. Your board may have support for up to a certain number of sides per ram at max speed. For instance you may only be able to dual channel 4 sides of ram total... or something along those lines. That is something that should be considered as well.

3) Speed: Ram comes in many speeds. You want to get the fastest your board can support. THis is front side bus, not processor speed. This is limited by your chipset and processor, and exactly what speed they run at. For instance if your CPU runs at 400Mhz FSB, you would like PC-3200 DDR ram. Now, if your chip runs at 333Mhz, you can use 3200 or higher, but it will throttle back to PC2700(333Mhz). You cannot have faster ram than your front side bus. But try to do max, if your board only supports 2 at 3200, then it is best to do 2 at 3200, rather than getting a 3rd stick to much things up, especially int he case of:
Dual Channeling... If you board supports Dual Channeling(and your processor does too) you can Dual Channel, which runs 2 matching sticks(speed and size) together to essentially double their perceived read/write speed. IT doesn't really matter whether you get how it works or not, just know if your board can do it, it is well worth your while to do it. The performace gain on high end applications like Gaming, programming, databasing, multitasking, is very nice. On Intels they tell you the doubled FSB when it supports Dual Channeling, for instance 800Mhz FSB means Dual Channeled PC3200(2x 400Mhz = 800Mhz). 1066Mhz is Dual Channeled PC3500(2x533Mhz=1066Mhz). AMDs didn't do that, so 533Mhz is PC3500, and when you dula channel it, you dual channel it, it is just how they labelled it as opposed to Intel. Only certain chipsets can do it... the lowest end chipsets don't handle it, and early ones don't handle it stably. But that is a whole story itself. For now, just see if your board supports it or not. If it does, 1 Gig dual channeled would run far faster than 1.5Gig total, so unless you need more than 1 gig for massive hog applications, stick with 1gig and dual channel that baddy.

4) CAS: Your latency/timing. This can be changed on most boards, but most people prefer getting CAS 2, because it is a tighter timing, which they think makes it faster/better. That is not entirely accurate, it is best to match it with your CPU/chiset's preferred CAS setting. It may be 2, 2.5, or 3. If you set it too tight and your board wants 3 CAS, then you are only hurting your speed and timing by setting it that way. That said, many times when you are Over CLocking, you are doing so using parts you know will do it, which usually tend to be CAS 2, which is kind of the basis of the myth of lower CAS = faster speed.

5) Quality: Your board, believe it or not, may have a need for a certain quality of ram. My gaming tower for instance cannot dual channel more than 4 sides(to a max of 1 gig) of PC3200 of the kind I originally bought for it, Buffalo, which is essentially low grade budget quality ram. However, I can dual channel 2 gigs of PC3200 of High end ram(Crucial XMS, which I have in there now). So depending on your needs, think about how good is the ram you are buying, really? Sure chieaper can be better, but it can also be just cheaper. But for many uses, you dont' need high end ram, so don't waste the money it.

WOW... thanks... that really clarified a lot!!!

After taking a look around in the different online stores (and once again reading through the mobo's user guide booklet), I think I'll go for a single TwinMOS 1024MB stick (CL 2.5, PC3200). I saw it got some really good reviews and isn't too expensive in comparison to two 512MB sticks.

3) Speed: Ram comes in many speeds. You want to get the fastest your board can support. THis is front side bus, not processor speed. This is limited by your chipset and processor, and exactly what speed they run at. For instance if your CPU runs at 400Mhz FSB, you would like PC-3200 DDR ram. Now, if your chip runs at 333Mhz, you can use 3200 or higher, but it will throttle back to PC2700(333Mhz). You cannot have faster ram than your front side bus. But try to do max, if your board only supports 2 at 3200, then it is best to do 2 at 3200, rather than getting a 3rd stick to much things up, especially int he case of: Dual Channeling... If you board supports Dual Channeling(and your processor does too) you can Dual Channel, which runs 2 matching sticks(speed and size) together to essentially double their perceived read/write speed. IT doesn't really matter whether you get how it works or not, just know if your board can do it, it is well worth your while to do it. The performace gain on high end applications like Gaming, programming, databasing, multitasking, is very nice. On Intels they tell you the doubled FSB when it supports Dual Channeling, for instance 800Mhz FSB means Dual Channeled PC3200(2x 400Mhz = 800Mhz). 1066Mhz is Dual Channeled PC3500(2x533Mhz=1066Mhz). AMDs didn't do that, so 533Mhz is PC3500, and when you dula channel it, you dual channel it, it is just how they labelled it as opposed to Intel. Only certain chipsets can do it... the lowest end chipsets don't handle it, and early ones don't handle it stably. But that is a whole story itself. For now, just see if your board supports it or not. If it does, 1 Gig dual channeled would run far faster than 1.5Gig total, so unless you need more than 1 gig for massive hog applications, stick with 1gig and dual channel that baddy.

False in many ways. For a FSB of 400 MHz, a 433 MHz or PC3500 is better. Motherboard manufactures that state PC3200 is wrong because setting the memory bus to 400 MHz needs memory that can handle faster than that. How well the voltage regulation, heat, bus frequency, and the quality of manufacturing changes the characteristics of memory so memory that is stated at PC3200 actually is between 380 MHz to 390 MHz. You can can buy PC3200 but you are not getting the full 400 MHz spec. If you squeeze a little more money out of yourself for PC3500, the 400 MHz bus can go at its full speed although it will not give you 433 MHz.

AMD's Athlon64 processors state dual-channel with the socket type. Socket 754 is single channel. Socket 940 and 939 are dual-channel. Socket A is single channel but chipsets like the nVidia nForce2 or VIA KT880 bridges the single channel to dual channel memory.

PC800 and PC1066 for Intel processors does not mean that it has dual-channel memory. It just a quadpumped spec which is 200 MHz for PC800 and 266 MHz for PC1066. You have to find out the chipset that is being used. Intel's 845 chipset is single channel memory. 850, 865 and 875 are dual channel memory chipsets.

Dual channel memory setups works better if there is an even number of memory modules. To get 1.5 GB out of dual channel memory, you have to have two 512 MB and two 256 MB, so a total of four memory slots will be used.

PC4000 is 500 MHz not PC3500.

OCZ Peroformance 1GB (OCZ4331024PFDC-K) should work and they are lot better than TwinMOS.

I totally disagree with you, and so does definition of the hardware, every major help site, motherboard and ram manufacturers, and basically the entire computing industry. Max speed is max speed. Since the originall DDR266, there has been no stability problem which would lead one to need the higher speed/grade of ram to run smoothly. That was only true on early AMD motherboards supporting DDR, usually on the KT266 chipset.

Ever since these days, using a higher grade has merely auto dropped it to the normal speed, and run it identically in every way to the proper version. Running memtest looped will show you the stability, or go ahead and run a few benchmarks like PCmark05, you will see the memory scores are identical, because the motherboards can't make use of a higher speed.

You are limited to the lowest factor between chipset, processor and ram. Having one above the others does nothing for you. A 333Mhz board and processor run 400Mhz at 333Mhz speed with no gain whatsoever. A 400Mhz board with a 333Mhz FSB chip and ram, runs both at 333Mhz.

I have no idea where you heard PC3200 ram is 380Mhz to 390Mhz, but I assure you, as a person who used to work as a tech in a store, and now does all my own work and have built a few hundred PCs from scratch, all PC3200 ram I have seen is 400Mhz, if yours wasn't you got ripped off pure and simple. PC3200 is 400Mhz, and that is how it has been since its release.

AMD's 64 bit sockets, the 754 and 939 delineate a lot more changes than merely the ability to dual channel, but I won't bother getting into that, since it is really moot. Either way, the ability to dual channel and memory management altogether was moved away from chipsets with the Athlon 64s, it is not chipset based, they put it directly into the processor, a move many think was horrible. Espeically given the first gen of these chips couldn't dual channel at all, which made no sense. The sockets have nothing directly to do with dual channel though, Socket A isn't singe channel, it is about the chipset, which contains the memory controller. Many of the early chipsets didn't dual channel at all, the nforce was the first set that did. Later via revised its KT333 and KT400 chipsets and relased later ones which did indeed have dual channeling ability.

Intels are far more than the base chipsets. It says very little to say you have an 865, that isn't the really important part. The G, P, PE, etc is the important part. The base 845 didn't dual channel, the P and PE versions of the chip do. The 865 and 875(the only other desktop series) do, and ahve many other enhancements and changes. The G version indicates onboard graphics, and changes very little aside from that. And no board allowing an 800MhzFSB ISN'T dual channel, period, unless you are dumb enough to get a via chipset on your intel-based board, a VERY bad mistake. Sis it a horrible mistake too. Intel makes the based chipsets in the world, and for their processors, you don't want anyone else making the chipset powering it. You will note AMD doesn't make chipsets.

By defintion Dual Channel works like rambus. It doesn't work better in pairs...it only works in pairs, period. You cannot dual channel a single stick of ram. THis is why you cannot use 3 sticks to dual channel, becaus eyou would be having 2 dual, and one solo. Which again, the lowest point is where everything runs. Thus with that spare stick, nothing dual channels.

I agree that OCZ PC3200 is a batter brand, but frankly when you have a 333mhz processor, there is no reason to shell out big bucks for Crucial XMS or OCZ ram, It won't do anything for you over Buffalo or basic Samsung or Kingston.

Originally posted by RedShirt By defintion Dual Channel works like rambus. It doesn't work better in pairs...it only works in pairs, period. You cannot dual channel a single stick of ram. THis is why you cannot use 3 sticks to dual channel, becaus eyou would be having 2 dual, and one solo. Which again, the lowest point is where everything runs. Thus with that spare stick, nothing dual channels.

You should check out the specs of the nForce2 chipset. It supports Dual Channel with 3 DIMMs.

It isn't Dual Channeling though. They can call it that, but that isn't what it is. And a single chipset breaking a convention is nothing new. That is like calling a car that drives with 3/4 wheels All Wheel Drive. They could call it whatever they want, doesn't change the fact that by definition, it isn't.

what is pc3200 ?

Originally posted by RedShirt I totally disagree with you, and so does definition of the hardware, every major help site, motherboard and ram manufacturers, and basically the entire computing industry. Max speed is max speed. Since the originall DDR266, there has been no stability problem which would lead one to need the higher speed/grade of ram to run smoothly. That was only true on early AMD motherboards supporting DDR, usually on the KT266 chipset. Ever since these days, using a higher grade has merely auto dropped it to the normal speed, and run it identically in every way to the proper version. Running memtest looped will show you the stability, or go ahead and run a few benchmarks like PCmark05, you will see the memory scores are identical, because the motherboards can't make use of a higher speed. You are limited to the lowest factor between chipset, processor and ram. Having one above the others does nothing for you. A 333Mhz board and processor run 400Mhz at 333Mhz speed with no gain whatsoever. A 400Mhz board with a 333Mhz FSB chip and ram, runs both at 333Mhz. I have no idea where you heard PC3200 ram is 380Mhz to 390Mhz, but I assure you, as a person who used to work as a tech in a store, and now does all my own work and have built a few hundred PCs from scratch, all PC3200 ram I have seen is 400Mhz, if yours wasn't you got ripped off pure and simple. PC3200 is 400Mhz, and that is how it has been since its release. AMD's 64 bit sockets, the 754 and 939 delineate a lot more changes than merely the ability to dual channel, but I won't bother getting into that, since it is really moot. Either way, the ability to dual channel and memory management altogether was moved away from chipsets with the Athlon 64s, it is not chipset based, they put it directly into the processor, a move many think was horrible. Espeically given the first gen of these chips couldn't dual channel at all, which made no sense. The sockets have nothing directly to do with dual channel though, Socket A isn't singe channel, it is about the chipset, which contains the memory controller. Many of the early chipsets didn't dual channel at all, the nforce was the first set that did. Later via revised its KT333 and KT400 chipsets and relased later ones which did indeed have dual channeling ability. Intels are far more than the base chipsets. It says very little to say you have an 865, that isn't the really important part. The G, P, PE, etc is the important part. The base 845 didn't dual channel, the P and PE versions of the chip do. The 865 and 875(the only other desktop series) do, and ahve many other enhancements and changes. The G version indicates onboard graphics, and changes very little aside from that. And no board allowing an 800MhzFSB ISN'T dual channel, period, unless you are dumb enough to get a via chipset on your intel-based board, a VERY bad mistake. Sis it a horrible mistake too. Intel makes the based chipsets in the world, and for their processors, you don't want anyone else making the chipset powering it. You will note AMD doesn't make chipsets. By defintion Dual Channel works like rambus. It doesn't work better in pairs...it only works in pairs, period. You cannot dual channel a single stick of ram. THis is why you cannot use 3 sticks to dual channel, becaus eyou would be having 2 dual, and one solo. Which again, the lowest point is where everything runs. Thus with that spare stick, nothing dual channels. I agree that OCZ PC3200 is a batter brand, but frankly when you have a 333mhz processor, there is no reason to shell out big bucks for Crucial XMS or OCZ ram, It won't do anything for you over Buffalo or basic Samsung or Kingston.

Go talk to an engineer about memory speed and bus speed. Smart engineers will use 2.3 ns RAM (about 433 MHz) for a 400 MHz bus or 2.5 ns RAM for a 333 MHz bus. For example, ATI uses faster RAM so there is no artifacts in the video output. If you increase the memory clock at the same speed that the memory chips are stated, you soon get artifacts as heat comes into effect. My nVidia GeForceFX 5700 Ultra uses a tid bit faster memory (455 MHz or about 2.2 ns) than it is clocked at (900 MHz or a true clock of 450 MHz). If you use a frequency counter, you will understand why you need to buy faster RAM than the bus.

G, P, PE does not mean it is dual-channel memory or not. They are different flavors of the chipsets that Intel focus on certain buyers. G uses on-board graphics, P adds performance tweaks and does not include on-board graphics, PE adds extreme performance tweaks and does not include on-board graphics. 845 chipsets does NOT have dual channel memory support. 850, 865, 875, and up has dual channel memory support. Read INTEL site and do not get confused by the data bits because SDRAM and DDR are 64-bit memory modules. At the time of 845 and 850 you have to invest in either 850 or 850e great game and workstation performance. If 850 and 850e was too expensive, you are told to wait a little longer for 865 and 875 or get an AMD system. At the time that 850 and 850e came out, I recommend these over 845 chipsets. You can do a search to verify that I did recommend them a few years ago.

VIA KT333, VIA KT400, KT600 are single channel memory. Again visit VIA site. The only chipset that is dual-channel from VIA for the socket A (462) is KT880. There is no point using dual-channel chipsets for socket A systems because the AMD Athlon processor has a maximum bandwidth of 3 GB per second. A VIA KT600 is the best one for both budget and performance. nVidia nForce2 only deceases the memory latency but never helps to gain extra memory bandwidth because it is all used up. It is like pushing an elephant down a pipe that is 1 meter in diameter. I also recommend either nForce2 and KT600 but it depends how much people want to pay for at the time.

I'll say it again dual-channel memory setups can handle more than two memory modules but only if even numbers (2, 4, 6, 8, 10) of memory modules are the same capacity. Also you can mix the capacities but it can not effect the first rule of dual-channel memory setups. nVidia's nForce2 should contain either two or four memory banks. Because of engineering and real world conditions, it is limited to three memory banks if no buffer chips are used. To get four memory banks out of an nForce2 chipset, buffer chips have to be included which increases the cost of the motherboard.

AMD Athlon64 is either single channel memory (64-bit data) for 754 sockets or dual-channel memory (128-bit data) for 940 and 939 sockets although 940 includes 16-bits for ECC. There is no difference between chipsets that has dual-channel memory and Athlon64 processors that has built-in memory controller that does dual-channel memory. AMD is just improving the steering wheel. AMD has been improving INTEL processors since they added 80x86 processors to their family with the 80386.

The poor JEDEC standards got tested when AMD introduce their 64-bit processors. Memory companies had to re-design their memory modules to work well with these processors or else go out of business. Whatever you point your finger to, but I point my bird to JEDEC. AMD also went to the drawing boards to perfect the memory controller in their processors. The JEDEC spec is a false advertisement, so do not count on PC3200 memory that does not actually run at 400 MHz. Look at the accessing time because it is a true specification of memory speed like it has in the old days of computing.

I'm not going to repeat myself in the next post.

I'm not going to get into the "speeds and feeds" fight, as I'm unqualified to comment.
However, Linux seems very sensitive to mixed memory - for example see this thread. A quick search should bring up more examples.

Be cautious is all I say.

You can mix brands but in dual-channel memory setups it gets picky. The problem johnb4467 may have is that the poster was using an odd setup for dual-channel memory chipset. You can not use 1 gigabyte with a 2 gigabyte memory module for dual channel memory systems. To get 3 GB of memory, johnb4467 should have used two 512 MB and two 1024 MB memory modules. The 512 modules can be Kingston and the 1024 MB modules can be Corsair.

Right now I am using two Samsung 256 MB of RAMBUS ECC memory and two Simple Tech 256 of RAMBUS ECC memory for a total of 1 GB of memory.

Originally posted by RedShirt I have no idea where you heard PC3200 ram is 380Mhz to 390Mhz, but I assure you, as a person who used to work as a tech in a store, and now does all my own work and have built a few hundred PCs from scratch, all PC3200 ram I have seen is 400Mhz, if yours wasn't you got ripped off pure and simple. PC3200 is 400Mhz, and that is how it has been since its release.

RedShort is absolutely correct, of course, but Electro isn't completely wrong, just pompous.

Most memory modules (nowadays) actually support multiple frequencies and timings. I'm using PC3200 in a PC2700 max laptop, for example, because @ 333 it allows CAS 2.5 instead of the reseller's stated max of CAS 3 @ 400. In fact, if you use a prog like CPU-Z (under Windows, sorry) you can actaully see the various bandwidth/timing combinations the module supports (which is how your mobo auto-configs it BTW.) So, in short, though the bandwidth remains the same, reducing latency does increase throughput. How much that improves real world performance depends on the application. You probably won't notice any difference surfing the web or writing OpenOffice doucments, but play a memory intensive 3D game and you'll get about a 5% FPS boost for that half a CAS #.

Mixed memory isn't such a big deal. My linux box currently uses 2x128 PC800 rambus of one brand, and 2x256mb PC600 rambus of Samsung, a total of 768 running at 400Mhz. So different speeds, different sizes, and different brands. They are hardset to 400Mhz in the BIOS(which is teh max FSB of my processor anyway.) So long as you hard set the speeds, they will play nicely. Just to test, I set it to auto, and boy oh boy... immediately upon rebooting, you could see it was running at 300Mhz instead of 400, then I got in to KDE once, where upon it froze immediately, then I couldn't boot all the way in again. I ran mem test and got massive errors. So I hardset them again, and they all play nicely, no memtest errors, and no problems booting and running cleanly. Hardsetting rams of different speeds can be the key, as it forces the board's memory controller to make them play nice.
The same goes for DDR and dual channeling, the less you leave to chance, the better. hardset them, and totally different modules can do just fine.(So long as you are hardsetting them to something they can both handle.)