Matching ram with processor FSB

Woden

hi i was wondering if i buy a barton processor should the ram i get be definetly be matched frequency wise with the fsb or should i buy higher frequency ram and run them asyncronously?

Does running them asyncronously give me the opportunity to run them syncronously if i decided to overclock the processor?

Also what latency is typical these days for 333mhz ram is it CL2.5 or CL2.0 and would i see much performance difference if i paid extra money for CL2.0?

I have to say i'm a bit confused by all the different types of ram on the market would this be something like what i was looking for?
http://www.komplett.ie/k/ki.asp?action=info&p=29912&t=1014&l=2&AvdID=1&CatID=17&GrpID=9&s=pl

Cheers

Data

zepp

you can runn faster memory at a lower speed so you might as well go for the best you can offerd .you can always use it again (not sure what memory the athlon 64 uses) .if your going for an athlon the top at the mo is i beleive 3200+ with a 400mhz bus so pc3200 will run that at its full potential.the pc3200 does give you the opertunity to over clock .i think you can get pc3500 now i think at above 400mhz

what chip you thinking of geting

anything about latency i haven't the foggiest

Sir Random

If your going with AMD, synchronous RAM is a must. Only the P4 supports asynchronous RAM with no performance loss.
It's worth paying extra for the CL2.0 if you intend to overclock (I presume you do if you're getting a Barton). You'll need to get faster RAM than the Barton and raise the fsb to match it or overclock it, but 1:1 is your only divider option for max performance.
My DDR400 is running at 416Mhz (2x208) but I had to loosen the timings (2.5,6,3,3) because it's cheap 2.5CL RAM. I'm gonna invest in some Mushkin PC3500 CL2.0 and hopefully push my 2.4 cpu over 3.5Ghz

Eurorunner

get yourself over to crucial - a short chat with their online support reps will insure that your ordering the right sticks. Service and price are great - I ordered a stick last Tuesday at 4pm and it was in my hands at 11:30am next day - unreal when you consider it came from Glasgow and im out in the sticks. Well worth it for the 5 quid delivery charge

Woden

thanks for the replies i'm thinking of getting a 2500+ i will be buying around the end of the month i will probably wait for the athlon 64 to come out to see if it drops the barton 2800+ into my price range.

I think i will pay for CL 2.0 ram and if i can afford it i will get ram with a frequency higher then my fsb so i can attempt to overclock it a little, *** i probably wouldn't bother overclocking until i felt the need like it couldn't keep up with the latest games or something

Sir random what do you mean with regards to timings?
and what do all the numbers like 2.5, 6, 3, 3 mean?

Sir Random

Those numbers refer to the RAM timings. It's the number of clock cycles taken to perform each step of accessing a piece of data from your RAM. Think of them as delays, so lower is better.
Using lower rates is known as tightening your RAM, raising them is referred to as loosening.

CAS (2.5 or 2) = Lower gives significant performance increase
tRAS (7,6 or 5) = Lower gives very small performance increase
tRCD (2, 3 or 4) = Lower gives significant performance increase
tRP (2, 3 or 4) = Lower gives very small performance increase

You can adjust these settings manually in your BIOS to maximise your RAM efficiency. Some mobos have RAM performance tweaking already in the BIOS. The Abit IC7 & IS7 have GAT (Game Accelerator) which has settings like "Turbo", "F1" & "Streetracer". These settings progressively tighten the RAM speeds for you.
I can get down to 2,5,2,2 at stock cpu speed but when I overclock my cpu, I have to loosen the RAM timings back to 2.5,6,3,3 because it's cheap manya RAM

I hope that makes sense.

Woden

thanx for the info sir random, i only seem to see CAS around so i'll probably go for that i think i will get CL 2.0 here is the stick i'm thinking of getting

http://www.komplett.ie/k/ki.asp?action=info&p=31386&t=1014&l=2&AvdID=1&CatID=17&GrpID=9&s=pl

does this seem ok to you? the timings seem quite low, if may get the equivalent 400mhz version if i have the money and i'm thinking of overclocking

i'm aware that typically in an dual ddr system is it two sticks are better then the same amount in one stick, but i figure i can get another half a gig later if i have the money?

Sir Random

I'd go with 2x256 sticks so you can take advantage of the dual mode but I suppose if you need 1Mb, you may as well get 1x512 for now.
What speed Barton are you thinking of? would you not be better off with DDR400 RAM?

Woden

i'm thinking of the xp2500+ at the moment its in my price range, if the xp2800+ comes down with the release of the athlon 64 i will get that, i may wait for an nforce3 pro motherboard also