Using multiple memory with different timings

[bluefoam]

I just dropped in another 2gb of basically the same memory I had before but with lower latency and without the led. The system was stable before but not so when running both pairs. My existing system had 2x1gb pc6400-800mhz twinx xms2"pro"running stock at 5-5-5-12 (1.8v I think). I picked up a pair of 1gb xms2 (no pro this time) pc6400C4-800mhz that is said to run stock and stable at 4-4-4-12 (2.1v). Tried this setting and have hangups, blue screens, and restarts when running both pairs together. Im assuming that when I set the timings in the bios that perhaps the older mem is also being changed to 4-4-4-12 too and may be creating the problem just like if the new mem were set to 5-5-5-12. Running either pair alone at their reccomended timings is no problem, but I notice that they don't play well together.

So...
Question 1 = is it possible to set timings per slot pair? If so, Im not finding it in award, or nForce.
Question 2 = has anyone found a mutual timing setting?
Question 3 = is it probably a better idea to switch out one of the pairs for something that runs optimally at the same latency????

thanks.

 

[myocardia]

Originally posted by: bluefoam
Question 1 = is it possible to set timings per slot pair?

No, it's not possible with any motherboard.

Question 3 = is it probably a better idea to switch out one of the pairs for something that runs optimally at the same latency????

You could do that, or you could do what most people do-- manually set your timings and vdimm in the BIOS to the higher of the two (5-5-5-15), and 2.1v.

 

[bluefoam]

Originally posted by: myocardia
You could do that, or you could do what most people do-- manually set your timings and vdimm in the BIOS to the higher of the two (5-5-5-15), and 2.1v.

Yeah... I was pretty sure that was the bottom line and stupid questions are asked all day everyday so I guess I had to slip mine in. Thanks for the quick response dude!

So I replaced the c5 with c4 Dominator to match the regular c4 xms2 and problem solved. Only thing is that its @ 2.17v and DDR3 should run at about 1.5v but this is now and only DDR2

oh well... fast enough for today and great pricing.