Higher rated RAM almost always 'works' with motherboards which are specified to 'work' with lower rated modules. It will simply be operated at the lower speed, which is what you want anyway! You should never really run your RAM at higher speeds than that required to 'synchronise' with the front side bus speed of your processor. Doing so can cause performance drops.

Having RAM modules which can operate at higher clockspeeds, however, allows you to overclock by increasing the processor's front side bus peed, and still have your RAM operating 'in sync' with it, and thus at its full efficiency :)

Didn't want to hijack the other thread with this question, so starting a new one here.

Interesting topic that you've brought up here. I don't want to hijack this thread, but just need clarification. If I've got a chip with a 333 FSB, and I'm running 400mhz RAM, what type of performance would I get by lowering the speed of my RAM down to 333? Would it even make any difference?

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If your PC is an Athlon XP, then it could make quite a noticeable difference. If it's a Pentium 4 or Athlon64, then it may not make as much, because memory management is a little better for those, i believe (haven't checked it in practice).


Best approach is to run sime benchmarking tools, change the settings for RAM speed, and then run them again to see how much difference it makes.

The last time I tested my self was with an XP3000+ system, GF4 Ti4200 display card, and using 3DMark2001, which is the best of the 3DMark test to assess overall system performance rather than just the display card.

Running RAM at 333MHz rather than 400MHz consistently made a difference of about 300 to 400 3DMarks to the test results, which isn't a helluva lot, but is certainly enough to show that the system wasn't working at full efficiency.

If your PC is an Athlon XP, then it could make quite a noticeable difference. If it's a Pentium 4 or Athlon64, then it may not make as much, because memory management is a little better for those, i believe (haven't checked it in practice).


Best approach is to run sime benchmarking tools, change the settings for RAM speed, and then run them again to see how much difference it makes.

The last time I tested my self was with an XP3000+ system, GF4 Ti4200 display card, and using 3DMark2001, which is the best of the 3DMark test to assess overall system performance rather than just the display card.

Running RAM at 333MHz rather than 400MHz consistently made a difference of about 300 to 400 3DMarks to the test results, which isn't a helluva lot, but is certainly enough to show that the system wasn't working at full efficiency.

Well there you go.

I'm running a Barton Athlon XP, which I'm not planning on overclocking at all. I'll try clocking my memory down, and see what I come up with. I'm running Sandra to benchmark with, is 3dmark better, you think?

3DMark is a gaming benchmark. 3DMark2001 is the best of the range for assessing more than simply the performance of the display card.

Other benchmarking tools would be more useful for measuring potential impacts on other computing activities, but of course for detecting the performance impact of running RAM 'out of sync' with the processor, any results relating to 'Memory performance' would need to be discounted. It only stands to reason that those ones would suggest a better result for faster RAM :D

My second PC is running at 400Mhz, 128MB ram. It is an OptiPlex GX1 from Dell. Just wondering what you would suggest is the best way to speed it up. It does accept up to 768MB ram but the processor is slow. Is overclocking going to give me noticeable results? Thanks!

My second PC is running at 400Mhz, 128MB ram. It is an OptiPlex GX1 from Dell. Just wondering what you would suggest is the best way to speed it up. It does accept up to 768MB ram but the processor is slow. Is overclocking going to give me noticeable results? Thanks!

You might want to repost this in a new thread. This discussion is regarding 400mhz memory, not 400mhz processors.

But in a nutshell, about the only thing you'll want to do to speed up your system is install more memory, and consider using a different, faster hard drive, like a SATA or SCSI drive. Even if you just upgraded your system's hard drives and CD drives, you'd experience a slight increase in performance. A processor upgrade on that system is inadvisable, and you're not going to get any real speed gains from overclocking, if you even could overclock that system.

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