Can I have 1.5G on ECS RS482-m motherboard?

[ECS_user]

I tried to add memory to my PC which has an ECS RS482-m motherboard. I know that the board supports dual channel DDR and required two identical memory chip to get dual channel working. I had Kingston PC3200 512M in the the first DIMM slot and it's been working. So I was not running dual mode. I just bought a Corsair DDR chip. I put the 1G in first slot, the PC booted up showing 1G ram. I add the 512m to the second slot, the boot hangs at the screen showing RS482_M and ATI express 200 picture.
Is it possible to run 1.5G (with chips from different manufacturers) on this board ?

[Tonka777]

You should be able to make it run ok if you set the speed and timings to match the slowest stick.

Can you get into the BIOS before it hangs?

[ECS_user]

This is good news. Yes, I can get into the BIOs.
I am not sure if I am looking at the right option, the DRAM configuration is now set to
Timing Mode [Auto] .
What should I do in order to get the full use of 1.5G ?

[Tonka777]

You'd need to find out what each stick is rated for, and then set the BIOD DRAM Config to suit the slowest module.

[ECS_user]

Thanks Tonka777. I found out that my new 1G ram is rated cl3 where as my old 512M ram is rated cl2. With the BIOS setting in AUTO, it automatically sets the cl rate to 2.5 (make sense). But I believe 2.5 makes both sticks not happy. I changed the BIOS setting to manual and set CL to 3 as suggested and I now have 1.5G running. Thanks a lot for your help.

[Tonka777]

No probs, glad you got it working!