Mobo is downclocking DDR 400 Mhz memory to 333 Mhz

[DJQuanta]

Hello guys.

I've been running my computer with 512 MB of Corsair Value Select DDR 400 Mhz RAM since I built it. At boot time the Mobo reports that the memory it's indeed clocked at 400 Mhz.

Last week I bought another 512 MB memory module from a friend who is upgrading his computer, it's the same brand and specs (Corsair Value Select), but after installing it the Mobo reports that I have 1 Gig of RAM but clocked at 333 Mhz, any ideas why this happens?

I have the Bios configured for "AUTO" on all of the memory settings. If I try to manually change the memory clock frequency the only available values are: 100, 133, 166 and AUTO... 200 Mhz it's not shown.

You can see my computer's specs on my signature (old school BTW).

Thanks....George

 

[Peter]

This is perfectly normal ... as bus load increases, the feasible speed decreases. DDR w/ unbuffered DIMMs is specified for 200 MHz with a single DIMM, 166 with two, 133 with three (per channel). E-step Athlons and Semprons exceed this specification, and allow 200 MHz with degraded timings is when at least one of the DIMMs is single-sided - if they're both double-sided, or with your older processor, it has to be 166.

 

[RiBeNtRoP]

Do you have socket 754? If so, that's normal, when you install three modules of ram, automatically it goes down to 333mhz instead the 400mhz it should be working.

 

[Peter]

As I just outlined, it already happens with two, and it's absolutely supposed to be like that.

 

[DJQuanta]

Ohh I see.... yes they are both double-sided BTW.

Well... so I guess there's nothing to do here, too bad my friend didn't have a 1 Gig module... I could've get that one instead and give my 512 module to him. Thanks for all your replies guys.