Ram question

Guest · Post by **Guest** » Sun Jun 12, 2005 8:17 pm

Right now I have 2x256mb ddr266 running in dual channel mode. I have one free ram slot, so if I buy a 512mb ram stick, will I lose the dual channel or what?

Post by **Kills On Site** » Sun Jun 12, 2005 8:20 pm

Yes you will looose dual channel

Guest · Post by **Guest** » Sun Jun 12, 2005 8:27 pm

So is it worth it? Dual channel made my fps go from 170 to 173 in quake 3

Post by **Tormentius** » Sun Jun 12, 2005 9:01 pm

It depends on your opinion. RAM is cheap, so I'd recommend getting 2x512 and maintaining the best of both worlds.

Post by **FragaGeddon** » Sun Jun 12, 2005 9:35 pm

If you have 400mhz ram and they are in dual channel mode, do they just run at 200mhz?

Post by **Quebeth** » Mon Jun 13, 2005 1:52 am

I wouldn't think so.

And if I were you, I'd get rid of the Pc2100 RAM all together, go for atleast 1gig of Pc2700. Pc2100 is pretty slow for these days.

Post by **Tormentius** » Mon Jun 13, 2005 2:49 am

FragaGeddon wrote:If you have 400mhz ram and they are in dual channel mode, do they just run at 200mhz?

No they run at 400.

Post by **FragaGeddon** » Mon Jun 13, 2005 3:17 am

Hmmm, for some reason I can't get mine to run at 400mhz.

Post by **AmIdYfReAk** » Mon Jun 13, 2005 3:19 am

what cpu do you have?

some mobo's will lock off the DDR400 option if the fsb is not 166mhz+

Post by **FragaGeddon** » Mon Jun 13, 2005 3:23 am

http://www.fragageddon.com/temp/cpuz.htm

Post by **Kills On Site** » Mon Jun 13, 2005 4:40 am

Well FragaGeddon, you have a Athlon XP 3000+ with a 166 FSB, AMD uses a multiplier of two so when you bought it the case prolly said 333 FSB. Now if you look at the RAM part of your link you will see a FSB:DRAM as a 1:1 ratio. So even if you have PC3200 (DDR 400) it will only run at 166.6~ MHz to match your FSB.

Post by **FragaGeddon** » Mon Jun 13, 2005 7:04 am

I think I'm going with Intel next.

Post by **FragaGeddon** » Mon Jun 13, 2005 7:06 am

I probably don't have something set right in the BIOS.

Post by **Kills On Site** » Mon Jun 13, 2005 7:08 am

Well Intel runs a quad multiplier, so while Athlon XPs say 400MHz and actually run at 200MHz Intel says 800MHz and actually run at 200MHz also. That is why you ouse DDR400 (PC3200) on both Athlon XPs and P4s.
Of course your processor has a slower FSB then the top Athlon XP or P4s.

I don't know why they use different multipliers or what exactly the performace difference is

Post by **Kills On Site** » Mon Jun 13, 2005 7:30 am

FragaGeddon wrote:I probably don't have something set right in the BIOS.

Well from looking at your CPU-Z report you seem to have this proc Athlon XP 3000+ 333MHz FSB and that proc and yours have the same FSB and clock speed. Your RAM is running at a 1:1 ratio with your CPU and the timings of the RAM seem to be good. Remember you have DDR RAM that means Double Data Rate so while the numbers look off and really low the CPU and the RAM are operating at their best rates for each other.

Now if having your RAM run slower truly vexes you then you could change some BIOS settings, but overall right now you are running at peak performance. If you wanted to get the RAM and CPU running at 400MHz, or 200MHz as it might be, then you have two options that would keep the ratio of CPU and RAM at 1:1.

You could:

A. overclock the FSB of your processor to 200MHz. In doing this you would most likely need a good HSF if you have one and you would have to drop the CPU multiplier so the CPU speed would be about the same.
The problem is that newer Athlon XPs are multiplier locked so you could not do this.

B. Buy an Athlon XP with a 400MHz FSB, found here

Like I said though, everything is running good right now, as far as I can see on the CPU-Z report. It is not a horrible thing that your RAM is running slower then it can. Hell PC3200 is cheaper then PC2700 anyway, irony I know, but since it is more widely used and produced, it is cheaper. That is most likely why you have it.

Also Quebeth is wrong. PC2100 runs at 133MHz and it is used in Athlon systems with a 266 FSB and Intel systems with a 533 FSB.
You are running PC2700, PC2700 runs at 166MHz, it is used in Athlon systems with a 333 FSB. Your RAM is just running slower then it can, it doesn't have to run at PC3200 speeds.

Post by **Tormentius** » Mon Jun 13, 2005 3:11 pm

FragaGeddon wrote:I probably don't have something set right in the BIOS.

No, since your CPU is running at 333 FSB its normal for memory to run on a 1:1 ratio on dual channel systems. Running memory with dual channel enabled on an asynchronous clock speed can (and usually does) cause system instability.

Post by **FragaGeddon** » Mon Jun 13, 2005 3:52 pm

Well it's running at 200mhz now.
http://www.fragageddon.com/temp/cpuz1.htm

Post by **FragaGeddon** » Mon Jun 13, 2005 3:53 pm

I notice now that the FSB:DRAM is running at 5:6 now instead of 1:1.

Post by **Kills On Site** » Mon Jun 13, 2005 4:57 pm

Well your FSB:DRAM is no longer in unison. Like Tormentius said that can cause instability. I personally wouldn't try it

Post by **Tormentius** » Mon Jun 13, 2005 7:04 pm

FragaGeddon wrote:I notice now that the FSB:DRAM is running at 5:6 now instead of 1:1.

Bad idea. You'll note you actually get less performance that way too, even though the RAM is running at a higher clockspeed.

Post by **FragaGeddon** » Mon Jun 13, 2005 7:38 pm

Yeah I changed it back. Was actually thinking about that while I was out.
Anyways thatnks for all your input. :icon14:

Guest · Post by **Guest** » Mon Jun 13, 2005 7:59 pm

Quebeth wrote:I wouldn't think so.

And if I were you, I'd get rid of the Pc2100 RAM all together, go for atleast 1gig of Pc2700. Pc2100 is pretty slow for these days.

Yes, especially because my cpu fsb is 266mhz

Post by **Tormentius** » Mon Jun 13, 2005 10:10 pm

FragaGeddon wrote:Yeah I changed it back. Was actually thinking about that while I was out.
Anyways thatnks for all your input. :icon14:

You're welcome.