BIOS not posting when both stick used

Rehan · 31 Jul 2007 at 19:41

Hi,

I have:

1 x 1GB Corsair XMS3200C2PT
1 x 1GB Corsair CMX10243200C2PRO
Both have timings of 2, 3, 3, 6

MOBO: Asus A8N SLI Premium

When using only one of the sticks it works fine but when using both the BIOS does not even come up. I remember messing with timings when I only had one stick of 1GB but can't remember what I did. Here are the settings in the BIOS currently:

MemClock: 400Mhz
CAS (tcl): 2
Min RAS active time (Tras): 6T
RAS to CAS delay (trccl): 3T
Row Precharge time (trp): 3T
Row refresh cyc time (trfc): 13T
Read-to-write time (trwt): 5T
Write recovery time (twr): 3T
1T/2T memory Timing: 1T
DDR Voltage: 2.80V

Thanks in advance

jak731 · 31 Jul 2007 at 19:50

Mixing doesn't always work, especially if they have different ICs, try relaxing the timings or set everything to auto.

Rehan · 31 Jul 2007 at 20:41

I tried putting the timings to auto, tried lowering the timings to 3, 3, 3, 6, putting the command rate to 2T and lowering the clock to 333Mhz and a couple of times during my testing I managed to get to the BIOS screen where it froze. Has anyone got any ideas? Will I have to get a matched pair?

jak731 · 31 Jul 2007 at 20:47

Non matched pairs sometimes don't like to run in dual channel mode, you could try running them in single channel which might require a different configuration of slots to use on your motherboard.

Rehan · 31 Jul 2007 at 20:51

According to the Asus manual I'm supposed to run them in A1 and B1 slots, which are the first and third ones. Which slots would you suggest.

GeForce · 31 Jul 2007 at 20:55

I had this problem on my A8N-SLi Premium. Hate to say this, but it turned out to be a faulty motherboard.

Tried several sets of matched RAM sticks and nothing worked; in the end had to get the motherboard replaced.

Jon

jak731 · 31 Jul 2007 at 20:57

Their should be 2 different configurations, one for single channel and one for dual, if A1 and B1 are recommended for single then try it.

Rehan · 31 Jul 2007 at 20:59

Noooooooooooooooooooooooooo

When I use one stick I have to use use the B1 slot. The A1 slot was a little dusty, could that have something to do with it. Can I just try any of the other slots at random?

GeForce · 31 Jul 2007 at 21:02

A1 and B1 are used for dual channel.

You can try any other combination and they should (in theory) run in single channel.

Jon

Rehan · 31 Jul 2007 at 22:03

Good news, I have got things working using the A2 and B2 slots which use the same channel (Same colour). Are there any negative repurcussions to running the ram in these slots. In the asus manual it says you should run two stick using A1 and B1 but they don't work on my motherboard (Is it worth getting it RMA'd, how long does this take).

Also, so far I'm running on 400Mhz, 3, 3, 3, 8, 2T. Is it just a matter of trial and error with getting these timings down.

Finally, how do you know you are running in dual channel?

Rehan · 31 Jul 2007 at 22:06

Answered one of my own questions, the ram is running in dual channel. CPU-Z told me so. Is there any way to fix the A1 slot which seems to be faulty.