PC 2700 to PC 3200 upgrade worth the $$?

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shrinkboy

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I am currently running two mis-matched 512 mb sticks of 2700 (default agressive timings in an Asus A7N8X Deluxe) with an Athlon 2500 @ 3200, two Raptors in a RAID 0.
How much of a performance increase will I see by upgrading the RAM?
Anyone here done before-and-after benchmarking in a similar case, or know of any reputable benchmarks out there? ie, not just anecdotal upgrade stories or non-methodical quickie reviews.

Best response gets a stick of RAM named in their honor.
 
well, I'd say you wont get the performance increase your looking for. Your cpu and ram are matched at 333mhz. Increasing the ram to 400 may give you a loss, since everything I've read indicates the best performance is when you've matched buss speeds.

Quote:On both AMD and Intel platforms, the most performance benefits are seen when the FSB of the processor is run synchronously with the memory – Although Intel based systems have a slight exception, this is completely true of all AMD-supporting chipsets. When looking at the AMD-supporting chipsets async modes are to be avoided like a plague. AMD-supporting chipsets offer less flexibility in this regard due to poorly implemented async modes. Even if it means running our memory clock speed well below the maximum feasible for a given memory, an Athlon XP system will ALWAYS exhibit best performance running the memory in sync with the FSB. Therefore, a 166FSB Athlon XP would run synchronously with DDR333/PC2700 (2*166) and give better performance than running with DDR400/PC3200, despite its numbers being bigger.
This example shows running the memory at higher asynchronous speeds. Assume we have a Barton 2500+ which by default is running at a FSB of 333 MHz (166 MHz X 2) and we also have PC3200 memory which by default is running at 400 MHz. This is a typical scenario because many people think that faster memory running at 400 MHz, will speed up their system. Or they fail to disable the SPD or Auto setting in their bios. There is NO benefit at all derived from running your memory at a higher frequency (MHz) than your FSB on Athlon XP/Duron sytems. In actuality, doing so has a negative effect.

Why does this happen? It happens because the memory and FSB can't "talk" at the same speeds, even though the memory is running at higher speeds than the FSB. The memory would have to "wait for the FSB to catch up", because higher async speeds forces de-synchronization of the memory and FSB frequencies and therefore increases the initial access latency on the memory path -- causing as much as a 5% degradation in performance.

;) But, I you decide to try anyway...........gimme first try on a good memory sale!
 
Shrinkboy, you have some things to think about. First, if you buy 400 ram and leave the settings as they are, you will get no noticeable increase in performance and/or speed, unless the ddr400 memory have tighter timings than the pc2700.

If you are goign to tweak settings to utilize the new speed (POTENTIAL) of your new ram, you'd have to run the bus asynchronously, or you'd have to bump up the FSB for your processor, therefore overclocking your CPU. If you run asynch, you may lose performance, as monkey34 mentioned. AMD systems do not agree so much to running async as well as Intels do. I dont know what agressive timings are in a A7n8x deluxe, but i imagine it'd be something like 2.5-3-3-6. Those timings aren't very tight, if you have some higher quality memory, chances are you could *possibly* get to something like 2-2-2-6 (some people report 2-2-2-11 to actually perform [very slightly] better).

Since you mentioned you have your athlon 2500@3200+ (2.2.ghz) you are probably running your memory asynch (333/400) and you would probably be losing performance. If you're running your memory at 100% you are overclocking your memory to ddr3200 as is (which isn't a big feat). If you're satisfied with that i'd leave it as is.

If you are NOT running syncrhonous in regards to the FSB, i think you'd be pleasantly surprised in the performance boost, although the only truly noticeable differences will probably be in the numbers benchmarks put out. All in all, it's really up to you. Asynch on AMD = bad mk?

Edit: Monkey edited his post before i got in, it covers a lot of what i said..

basically: If you're running your 2500+ at 3200+, DDR 400 is what you want.
 
With AMD ... always always ALWAYS run synch! If you're running anything other than 1:1, you will have a performance decrease.

Since you say... 2500+ @ 3200+, I'm guessing that's 11x200? And you said your memory was running at PC2700? That's 166MHz. BAAD! Either change your multi so that you're getting a 166MHz FSB... (hmm... 13x166? 13.5? if your board/cpu supports it).

That, or upgrade to PC3200...
 
Intial messing resulted in some serious errors trying 200 mHz with the RAM- no combination of timing, voltage or swearing worked. RAM is back at 166.
Dropped the processor to 166x12 for some initial testing (shows as a 2700+) and increased my Futuremark score by 2 (yes, that's right, 2!) with an effective 500 mHz decrease in clock speed. There may be some potential here as I ramp the processor back up. Memory settings are something horrible, as the RAM is nasty, apparently- (23-15-15-9 or something equally high...) so I'll start shopping for some DDR400 here.

And forgive my little brain, but DDR400 = PC3500? I can never remember.
 
ddr400 = pc3200
ddr333 = pc2700

i have what was mentioned here, 2500+ at 166mhz and i can't even get a stable overclock at a 200fsb even with pc3200. i have it running at 400mhz just because i hate buying something that i won't ever use. but i don't really notice any difference at all.
 
Originally posted by HRslammR
ddr400 = pc3200
ddr333 = pc2700

i have what was mentioned here, 2500+ at 166mhz and i can't even get a stable overclock at a 200fsb even with pc3200. i have it running at 400mhz just because i hate buying something that i won't ever use. but i don't really notice any difference at all.
Click to expand...
Leave the RAM at 333 if your FSB is 333—you're degrading performance by running async like that.

Did you try upping VCore when overclocking the processor?
 
200/400 MHz => DDR400 or PC3200
217/433 MHz => DDR433 or PC3500 :D
 
Originally posted by Monkey34
well, I'd say you wont get the performance increase your looking for. Your cpu and ram are matched at 333mhz. Increasing the ram to 400 may give you a loss, since everything I've read indicates the best performance is when you've matched buss speeds.

Quote:On both AMD and Intel platforms, the most performance benefits are seen when the FSB of the processor is run synchronously with the memory...
Click to expand...
True, running Async is bad, but your missing something here. You generally want to buy RAM that will outpace your FSB, not because your running your memory at different speeds, but because your OCing and that increases the FSB. So if your system is a 333 based FSB, get 400 or better RAM if your OCing, the extra headroom will be used when you raise your FSB, keeping 1:1 ratio will also increase your RAM speed. If you match your RAM speed to your boards base FSB you will not be able to OC much, if at all.
 
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