Which ram is better for this system?

[CoolermasterKid]

Ram Slot 1 CMX1024 DDR2 6400

Ram Slot 2

Ram Slot 3 CMX1024 DDR2 6400

Ram Slot 4

 

I also have a matched pair of CMX512 DDR2 6400

 

My question is this:

 

When set to AUTO the ram speed is 6700 and when set to DDR800 it shows 5300 in the bios.

 

Why does this happen?

 

Would I be better to upgrade to

 

TWIN2X2048-6400C4DHX

 

or

 

TWIN2X2048-8500C5D

 

It seems that this board does not like all 4 slots full of ram, after trying the ram listed above and since I use this system to enlarge photos for billboards with Photoshop the choice of ram is important and I also need a stable system so with this processor I would rather leave it at the stock settings .

 

Any ideas or additional comments welcome. Thanks.

[DerekT]

Ram Slot 1 CMX1024 DDR2 6400

Ram Slot 2

Ram Slot 3 CMX1024 DDR2 6400

Ram Slot 4

 

I also have a matched pair of CMX512 DDR2 6400

 

My question is this:

 

When set to AUTO the ram speed is 6700 and when set to DDR800 it shows 5300 in the bios.

 

Why does this happen?

 

Would I be better to upgrade to

 

TWIN2X2048-6400C4DHX

 

or

 

TWIN2X2048-8500C5D

 

It seems that this board does not like all 4 slots full of ram, after trying the ram listed above and since I use this system to enlarge photos for billboards with Photoshop the choice of ram is important and I also need a stable system so with this processor I would rather leave it at the stock settings. Using DRAM sticks of different densities adds another variable to the instability possibilities though.

 

Any ideas or additional comments welcome. Thanks.

 

No boards like all four slots filled. The DRAM speed usually needs to be dropped to find stability. With 800Mhz DRAM a drop to 667Mhz is advised. Also a raise of the MCH Northbridge voltage is advised.

 

With 4 X 8500C5, you would need to drop to 800Mhz speeds. You could very likely set the timings of that DRAM to 4-4-4-12 and 800Mhz.