memory problems

[ragewind]

i have an asus crosshair mobo with 2 gig of dd2 ram and i decided to add another 2 gid ending up with 4x 1gig sticks.

problem is i get a bios error beep for memory error 1 long and 3 short beeps.

ive tried both pairs speratly and swapped both around thinking it was to do with the slot pairing for the dule channel mode seemed to be in the right slots to be paired as they manual says.

so have here is the info of both sets of chips have i got diferant types?
both are by corsair ddr2 sets, just not sure why my motherboard is bringing up bios errors when i try fitting all 4?

old

CM2X 1024 -6400 C4 4-4-4-12
XMS 6404 v2.1 800mhz
XMS2 -6400

new

CM2X 1024 -6400 5-5-5-12
1.90V ver 5.1 800mhz
1024mb

also if i have the wrong types can you recommend something to get that will work.

any help much appreciated.

 

[lord filbuster]

i think it is because the voltages for the ram modules are different, one runs at 2.1V the other at 1.9V, maybe you should exhange them for another matched pair which is the same as the old memory,http://www.overclockers.co.uk/showproduct.php?prodid=MY-108-CS&tool=3 i think this is the same. It is usually best to have all the ram modules of the same type, ive heard asus motherboards can be quite picky about ram.