how is it that pc400 (ddr500) ram works in pc3200 mobos?

[dalearyous]

im going to buy 2x1gig memory setup paired with amd chip. and here is my question, i see many people are buying pc400 (ddr 500)ram...but the mobo says it takes max of pc3200. common sense tells me that the pc400 ram is automatically down clocked and people buy it because they plan on overclocking right away and pc400 gives them more of a range. if thats true, is it better to buy the faster ram or buy the ram with better timings?

 

[bwcc]

It is more probable that the ram will not work in your system at all. I am not 100% sure on underclocking ram, but someone else in here may be able to explain how over/under clocking ram works.

Everything I have read recently points to looking at better timings over higher speed.
ie : PC2700 ram w/ 2-3-3-6 timings will perform better than PC3200 3-4-4-8 due to how may cycles it takes for the information to get to and from a memory module.

Even then, if you read a lot of hardware reviews, even timings do not make that much of a difference either. The biggest timing factor is the CAS Latency. Opt for a 2.5 or 2 CAS over a 3 or 4.

Best bet - overall would be to find a good set of PC3200 (DDR-400) with decent timings - such as Patriot or Corsair or Kingston. As far as going to 2GB of Ram, you may want to rethink that, pending on what you are using your system for. A good recent review of 'how much ram do I need' is available on Toms Hardware:

http://www.tomshardware.com/2005/12/13/...uch_ram_do_you_really_need/page12.html

Hope this helps some.

 

[dalearyous]

yeah i was already planning on getting OCZ ddr400 ram with 2-3-2-5 timing. 2 gigs is pretty much set in stone. the price difference isn't bad and with my new dual core i plan on doing a lot of stuff at the same time.

i would agree that a gig is plenty for right now. but if im building completely new computer why not. i may need it in couple years

 

[stevty2889]

There is no official JDEC spec for ram over PC3200, so thats why motherboards don't list it as supported. It will be backwards compatible, and work at slower speeds. Anything over PC3200 is really only good for overclocking. By defualt it will just run at PC3200 speeds. You would have to run your FSB at 250mhz to run the ram at it's rated speed, and of course you would be overclocking your CPU as well.

 

[aaqubit]

i'd just buy budget pc3200 ram. you don't need good ram to overclock--just use a memory divider. the difference in performance? on average, maybe 1-2%. but you save a lot on budget ram compared to ddr500 ram. just spend that extra money on a better video card or save a few dollars.

 

[Apocalypse X]

Originally posted by: aaqubit
i'd just buy budget pc3200 ram. you don't need good ram to overclock--just use a memory divider. the difference in performance? on average, maybe 1-2%. but you save a lot on budget ram compared to ddr500 ram. just spend that extra money on a better video card or save a few dollars.

yeah right...