Upgrade Choice--More Ram or Faster CPU

I built my system 18 months ago:

Gigabyte K8SN-939-Ultra
Athlon 64, 3000 CPU
DDR 3200 two sticks of 256

With the recent AMD price drops, I think it is time to upgrade. I’ve read threads where people say upgrade to 2GB Ram creates better performance than an upgrade to entry level dual core. My main interest is NOT games, but rather video encoding and multi-tasking. I’ve read comments that such performance IS aided by both faster CPU and more RAM so I think I’d like to upgrade RAM and then the CPU? ((Each upgrade should “feel” like a new computer to me??))

As a small aside–a friend just gave me a single stick of 256MB RAM and I can’t get a “clean” answer on this–I’ve read that AMD processors are so “efficient” that they don’t really benefit from DDR! On my motherboard, adding a third stick of RAM reduces the speed of the front bus ((don’t know how much–from 800Mhz to 400 I assume–anyone know?)) but I wonder==>

  1. which is faster–DDR/800Mhz running with 512MB RAM, or NOT DDR/400Mhz running with 512+256=768 RAM??

  2. Is 2GB overkill or would increase to 1GB be sufficient. I assume by time I upgrade to Vista, DDR2 will be mandatory?

  3. How can I get the FSB over 800MHz? My motherboard is variously described as capable of 1000 or 2000(!?!) MHz capable with hypertransport. Is the increase over 800Mhz achieved by “overclocking” or by buying compatible Ram–eg DDR4000?

Alot of questions/unknown assumptions/etc==thanks for any answers/directions etc. /// bobbo.

If you can’t afford to buy both RAM and CPU, I suggest you to buy first the CPU: with the same amount of RAM, a faster CPU give always (for what I know) better results than the increase or RAM memory.

That depends on whether the system has “enough” RAM memory for the tasks that you run concurrently.

If you have enough memory, then adding more memory won’t make the system (much) faster, and upgrading the CPU would be the better choice.

If you OTOH don’t have enough memory, then your system will be running much slower than it has to and upgrading the CPU won’t make much of a difference, whereas adding memory can make your system improve from a crawl to running at the full speed of the CPU.

The potential speed increase by upgrading the CPU can be measured as a percentage, perhaps as much as 50%.

The potential speed increase by adding memory to a system, that has too little memory and is using the page file excessively, has almost no upper limit since disk access is 100.000 times slower than RAM memory access.

For Video editing tasks 512 MB memory is not very much.

:o You’re right Drage

I was considering 1 GB of RAM as “standard” for a computer :doh:

I do some pretty heavy transcodes with dvd shrink, even with my overclock something like king kong can take over 2 hours, after a lot of testing I found that with 512 megs
running on a lean clean machine always had 100-150 megs free during the transcode,
but shrink was always using close to 100% cpu. I tested 1 gig of slightly slower ram,
my times with shrink increased. Multitasking and encoding don’t go together, unless you have dual core.

Good info all there–thanks. of course, we know upgrading “Everything” is the way to go. I’ve been very happy with my 512MB of RAM as that was an upgrade from my first computer using only 128MB which basically meant it couldn’t even “do” encoding (smile!)

Multi-tasking while encoding is “slow” but seems to mostly work. About every other day my system will have a “mini-freeze” with a Word or Excell document taking over 100% of cpu resources. Usually closing that program in task manager and reopenning the application takes care of the issue==anyone know if that is a direct lack of ram issue or something else?? /// bobbo

Edit -PS==I do try to experiment/learn as much as my budget allows. I think it will be informative and rewarding to two step the upgrade and if upgrading one element gives me all I want before going to vista, then why spend the additional money?? So right now its looking like indeed, more RAM atleast up to 1GB would show a meaningful difference? To rephrase one of myquestions then–would 4 sticks of 256 RAM be much different than 2 sticks of 512?? Balance–I would only have to buy one more stick of 256 but FSB would drop out of DDR BUT DDR supposedly is not that big an issue for AMD??? Meanwhile, I would have to buy both sticks of new 512 RAM. Any thoughts?? //// bobbo.

  1. You need to use the RAM sticks in pairs, 3 is not a good setup. Get two additional 256MB sticks (which aren’t too expensive) and you’ll have a total of 1GB.

  2. Increasing RAM size follows the law of diminishing returns. You’ll notice the difference between 512MB and 1024MB, but will hardly see a difference going from 1GB to 2GB (unless you do some very special things with your PC or play the latest games at highest resolution/quality). The AM2 platform with DDR2 533 or 667MHz currently doesn’t give a performance increase over S939+DDR400. Only DDR2 800MHz gives a slight advantage.

  3. This falls under overclocking indeed (and can’t be answered in a couple sentences - even if I knew the answer :wink: )

If you want to upgrade this machine go for the two additional (& identical) 256MB RAM sticks and an X2 processor. The CPU will give you the most.

Cressida–What you say makes alot of sense. I’m trying now to confirm that more than just the first two ram slots provide DDR. ie–filling up the 3rd and/or 4th slot loses the ddr doubling of ram effect. That was confirmed in some initial reading I did and with a talk at the good folks at Corsair, and as always gigabyte tech support could only tell me to upgrade to win XP.

Re #3–I’ve read the overclocking guides and “just for fun” tried to increase my FSB thru bios settings. 3 times now I just got a BLACK screen of death–so I’m kinda off the overclocking thing. Again–Corsair said that overclocking was part of it but that faster ram was needed as well. While “experts” – all their advice seens to always lead to buying the most ran you can from them (fair enough!).


I’m trying now to confirm that more than just the first two ram slots provide DDR. ie–filling up the 3rd and/or 4th slot loses the ddr doubling of ram effect.

that has nothing to do with ddr, just dual channel(5% speed gain?)

Now thats interesting–so a FSB running at 400MHz is only 5% slower (or would it be less bandwidth?–read as I do, the concepts aren’t clear to me as they do relate/interact with one another and are task dependent?) than the same amount of ram running at 800MHz? That is consistent with what lots of threads say about the AMD processor but not consistent with all the hoopla??

So–it sounds like cost wise it makes sense to add another free stick of 256 Ram and maybe buy a forth stick (all very cheap) rather than go for that extra 5% by buying two brand new sticks of 1GB RAM?

Thanks DaChew. I have a gut feeling you are right. Marketing hype should be clearly labeled as such??? (smile)=== bobbo.

It’s nearly always faster to have more RAM if you use part of the RAM space as HDD. Not only faster, but also much more silent.

filling up the 3rd and/or 4th slot loses the ddr doubling of ram effect.

totally wrong!

fsb at 200, ddr running at 400, 4x or 5x , HT running at 800 or 1000

1,2,3 or 4 sticks of ram irrelevant

nothing to do with dual channel and matched pairs

you aren’t grasping the concept, do some reading

Why do you think your HTT is at 800MHz? If you set your CPU speed at 200MHz and your CPU multiplier at 9 and then set your RAM frequency divider at 200MHz (1:1) and your LDT multiplier at 5X, you should be getting an HTT of 1000MHz as well as your stock clock on CPU and RAM.

When Vista comes next year it should not care if you have DDR or DDR2. The only time there is a benefit is if you get some considerably faster DDR2 as PC3200 is PC3200 in either case.

Hey DaChew–I read and read and the understanding only comes slowly. Can read about hyperthreading and intel and ddr and then read it has little to do with hypertransport and amd! Hard to gronk. ((I think “real” knowledge only comes when we get to put “hands-on” the equipment and I just don’t have that opportunity. Reading is great–but limited.))

Anyhoo, I think I have confirmed what you said just above at these two different websites which I post for those interested:


This all goes “against” my “common (uninformed) sense” that going from 512MB of Ram to 1GB only provides a 10-20% increase in content creation, and going from single channel to ddr only increases the speed by 20-30%. Not like a regular algebraic equation?

Crucial tech support and gigabyte website both declare that occupying the 3rd ram slot lowers the speed down from ddr3200 (and that actually makes sense–cant run three numbers in a double!). I believe but don’t firmly remember what they said about occupying all four slots but I think only the first two actually will operte in DDR mode. Could either of us be wrong??? I know I could be.

My conclusion–I’m going to confirm why the heck four ram slots wont run in ddr as “they ought to” then install that third stick of Ram and see what it does to performance. If there is any increase, gonna buy that fourth stick for 1GB total and then wait a year for my next build.

Thanks for the info and encouragement. Will keep reading and posting to this thread as new info is gained. /// bobbo.

Chas–I agree totally. I have gone to overclockers.com (?) and other sites, downloaded and printed their instructions and when changing the bios, all I get is a black screen of death. It might be something real simple I’m doing wrong, but its not working for me. I even understand and agree that what you posted should work. Maybe I have a bad motherboard??? (Blame the tools!!!).

I’m going to print your suggestions and give that a try. Who knows–I may need to upgrade my cpu sooner than I had planned??? //// bobbo.

So how do you know your HTT is at 800? When you do get a boot what are your BIOS settings, by default, based on what I suggested above?

Chas - - thank you. I responded to your post with a “longish” excuse, then changed my mind and grit my teeth and went into my bios. I changed the “CPU Clock Ratio” from 4X to 5x or from 800MHz to 1000Mhz and saved and exited. Then I rebooted back into the bios and the setting is still there at 1000–so I guess it has been reset without a hiccup or shudder. I really do wonder what in the heck I did those other times. Seems like every other area of change has to do with voltages so it must have been some of those settings?

My bios shows multipliers up to 1800Mhz, but I will stay at 1000 and monitor performance and cpu temperature for a few weeks. ((When should I change voltage? ((Running before I can walk he asks!))

Without your patience and multiple encouragement, I wouldn’t have made it===THANKS. //// bobbo.

Edit==Now I’m trying to understand what DaChew last posted. It makes sense–so what the heck “does” DDR mean in practical application? It does make a speed difference as the websites I posted reported? ((Make that rhetorical!)) 2nd Edit–course that website performance report was about an intel DDR setup==so “nevermind!” HT is based on clock multipliers. I hope I don’t forget this overnight. Thanks DaChew!!

DDR is double data rate, and has nothing to do with dual channel(which is using matched sticks)

200 membus becomes 400Mghz when doubled

you lose dual channel not double data rate when using mismatched sticks(eg 3 sticks)

here’s my overclock
CPU Properties:
CPU Type AMD Athlon 64
CPU Alias Venice S939
CPU Stepping DH-E3
CPUID CPU Name AMD Athlon™ 64 Processor 3000+

CPU Speed:
  CPU Clock                                         2519.77 MHz
  CPU Multiplier                                    9.0x
  CPU FSB                                           279.97 MHz  (original: 200 MHz, overclock: 40%)
  Memory Bus                                        251.98 MHz

      Memory Timings                                    2.5-4-4-10  (CL-RCD-RP-RAS)
  Command Rate (CR)                                 1T

SPD Memory Modules:
  DIMM1: Micron Tech.                               256 MB PC4000 DDR SDRAM  (2.5-4-4-10 @ 250 MHz)  (2.0-3-3-8 @ 200 MHz)
  DIMM2: Micron Tech.                               256 MB PC4000 DDR SDRAM  (2.5-4-4-10 @ 250 MHz)  (2.0-3-3-8 @ 200 MHz)

after setting the fsb up to 280 I then applied a memory divider to get my ram
to run at 250(it’s rated speed), I then lowered my hypertransport to 800
multiplier which gives me a 4 x 280, or 1120 hypertransport

solid for 8 months now

Chewy–for a hairy simian you sure throw your numbers around “with authority.”

Seems like you are multiplying and dividing and coming back close to stock values but somewhat better?? I’ll have to reread my sources and pay closer attention to when it says DDR versus dual channel.

With AMD cpu prices cut nearly in half over the past month, do you have any plan for a modest upgrade? /// bobbo.

Edit==and why stop the hypertransport at your setting==why not higher like 1600 or such?

the system will start to become unstable if you push the hypertransport past ~1100

from what I’ve read it doesn’t make much performance difference if the HT is overclocked or not, and some say it can even be underclocked and not hurt performance all that much, as long as it is 800+