Important Socket 754 Memory Question

[Kef9]

Im going to be building a new SFF s754 athlon system very soon. However I am not sure which memory to get as the s754 onboard memory controller runs in single channel mode only. I have no plans to overclock and so am only interested in stock performance.

There are 2 dimm slots on the mobo and there are 2 options.

Get a dual channel kit 2x512Mb, timings 2.5-3-3-6 and populate both dimm slots leaving no room for future upgrade.

or

Get 1 stick of 1Gb, timings 3-4-4-8 and leave 1 slot free for a future upgrade.

Now am i correct in thinking that if I poulate both slots I will have to use a CMD rate of 2T? If this is the case would the performance advantage of the lower timings of the 2x512 Mb kit be wiped out meaning I would be better off with the poorer timings of the 1Gb stick and a CMD rate of 1T.

Any help really appreciated.

[StormPC]

If you are not overclocking then you need fast memory and you need to run 1T. If you run 2T you will be losing even more bandwidth, something you can not afford on a single channel A64. A dual channel A64 has roughly twice the bandwidth so it's not as big a deal to run 2T, although there is still a loss of performance.

Get 2 sticks of good memory. 1GB (2x512MB) should hold you over for quite awhile. I suggest something with Samsung TCCD chips, like the Corsair PC3200XL or equivelant. They run 2-2-2-5 @ 410MHz on stock volts.

If you buy good RAM now it will last you for a long time, not to mention it will perform much better in your S754 system as well. If you go to a DC AMD or Intel platform later you can still keep your memory.

[Kef9]

Yep I understand all of what your saying but I'm trying to find out what happens if you populate two DIMM slots in a 754 system due to the fact that it only has a single channel memory controller.

I am aware that if you populate more than 2 DIMM slots in a 939 system you have to run 2T. Hence I am wondering what happens if you poulate more than 1 slot in a 754 system - Do you have to run 2T?

If so what I want to know is if you are better off running 1T with a single stick at poorer timings than running 2 sticks with better timings at 2T.

[StormPC]

You have been misinformed. The command rate (1T or 2T) has nothing to do with how many DIMM modules you use. S939 requires 2 modules to run in dual channel mode which is the only reason to buy S939. Anybody running a S939 with a single module is wasting his money big time.

Most S754 boards have 3 sockets for memory. Yours has only two because it is a microATX board so they are cutting costs. If you have a good chip you can run all 3 populated, but may have to run 2T in order to run at DDR400 (PC3200) speeds.

Two modules will run at full speed with no problem! I don't recommend 1GB DIMMs though. Stick to a pair of 512MB, or even 256MB (1GB or 512MB total) if you want the best performance. Only go 1GB if you are a hardcore gamer or work with very large images or other extremely large files. For most others 1GB is overkill.

[[DW]Cougho]

You have been misinformed. The commnd rate (1T or 2T) has nothing to do with how many DIMM modules you use. S939 requires 2 modules to run in dual channel mode which is the only reason to buy S939. Anybody running a S939 with a single module is wasting his money big time.

Most S754 boards have 3 sockets for memory. Yours has only two because it is a microATX board so they are cutting costs. If you have a good chip you can run all 3 populated, but may have to run 2T in order to run at DDR400 (PC3200) speeds.

Two modules will run at full speed with no problem! I don't recommend 1GB DIMMs though. Stick to a pair of 512MB, or even 256MB (1GB or 512MB total) if you want the best performance. Only go 1GB if you are a hardcore gamer or work with very large images or other extremely large files. For most others 1GB is overkill.

this fella has hit the nail on the head.

I run a S754 system with 2x512mb modules and run at 1T no problems.