Bandwith efficiency question

[skogkatt]

Hi,

 

I moved this week from AGP to PCI Express, and I have a question related to memory bandwith.

 

Today's system is in my sig, previous was MSI Neo2-54G mobo, Winchester 3200 and X800XT PE. All other parts are identical.

 

First I have to say I'm very pleased with the overclocking potential of the DFI. while my OCZ couldn't run over 256 Mhz on the MSI, I ran 10 hours of memtest last night at 295 Mhz (2,7V - 2,5-4-3-8).

 

So I booted into windows to see if it was stable there. But I had strange results when running Sandra memory tests:

It says "bandwith efficiency 67%" while I was near 90% with my previous rig.

 

I even have worst results @ 235Mhz with 2-3-3-8 timings (6081/6001) than on the MSI with 2,5-3-3-8 timings (6464/6374).

 

This translates also in a loss of 1600 points in 3DMark2001 for similar CPU/RAM speed (with a supposed better video card!).

 

Does it come from the Venice? or is there a parameter I'm missing somewhere in the bios? And would moving from slots2&4 to 1&3 help (with bios upgrade)?

 

My DRAM config :

200

Enabled

2,5

4

8

3

7

14

2

2

1

2

4708

Auto

 

Auto

0

7

2

7,0

Auto

256

Disabled

16

7

Disabled

 

Thanks for your help,

 

Skogkatt