My motherboard is P31-DS3L.
I got two memory sticks. each one of them is a 1GB 800MHZ memory stick.
one of them is Corsair Value and the other is Kingston's.
When i connect only one of them (no matter which one) the MB recognize it as it should be, a 1GB 800MHZ.
but when i connect both of them, it recognize i got 2GB 667MHZ connected.
For some reason the memory speed reduced.
My bios version is F8. so its not the problem i guess.
I connected them in the negative slots so they wont work in dual-channel, but it didnt help either.
I even increased the V by 0.3 and it didnt help.
what causing this problem and how can i solve it ?
(BTW, sorry if i got mistakes in my English )
the problem is that the sticks of ram you have are not identical. THey work, but you loose in speed. You can solve this problem by selling one of the two (or both) and get an identical one (or a new set of 2x1Gb modules). Try as hard as you can, you will never overcome this unless you use the same memory modules.
The reason is because you have 2 different memory brands. I doubt that the timings are set correctly as well. You PC has to be able to read the memory stick and set the correct timings and bus speed. With 2 different brands of sticks, it is getting conflicting information, or having a hard time reading it, so it kind "runs" to a default setting that will likely allow your system to boot and work.
You will need to go into your BIOS, disable the auto settings, and set everything, including the timings manually.
Memory rule #1. Don't mix brands or types of memory. Keep them all the same.
I had the same problem with a system I built for my sister. The memory was a matched set of ddr2 800. The problem was using the old power supply when I did a major upgrade. Not enough juice to make them work at the right speed so the under clocked themselves. ( 2.4p4/184 sdram/ to a core2duo/newboard + memory. power supply couldn't handle it )