ga-ma770t-ud3p won't turn on when all RAM slots are occupied

[richardjay]

I'm trying to upgrade my ga-ma770t-ud3p from 8gb to 16gb.

Previously I had Corsair 2gb sticks (one in each slot), so I replaced them with Corsair 4gb sticks but now the machine won't even get to BIOS when all 4 RAM slots are accopied. If I remove the stick in the 4th slot then the machine is fine (and I have 12gb RAM).

Any idea what this could be ?  Some kind of voltage problem ?  I flashed the BIOS to F12 (latest) and went with the default settings.

[Dark Mantis]

Generally you will need to increase the memory voltage to compensate for the extra loading of having all the slots filled. Usually it is about 0.05v more than the default. Make sure that you don't try and run the memory too fast though as there was a problem AMD had with the memory controller. 1333 or below should be fine.

[richardjay]

So the AUTO value won't increase the voltage to what is required  That doesn't seem to clever ...

Ok, so do you happen to know what the actual option is I need to change as there are a lot of options in the BIOS. Is it DRAM Voltage Control ?  Because that is already showing 1.600v and the RAM sticks say 1.50v ....

[richardjay]

Looks like I was barking up the wrong tree ....

The problem is not that the PC won't start if al 4 slots are used.

The problem is that the PC won't start if the 4th slot is being used. So even if I only have 3 slots used, if one of them is the 4th slot (furthest from CPU), then it won't post to BIOS.

I'm starting to think that I somehow damaged something when installing the new RAM 

[Dark Mantis]

It sounds to me like it is probably the memory controller that is actually at fault not the slot itself. What speed memory have you got ?

[richardjay]

Well, I hope you're right

But I don't see anything listed as Memory Controller. Memory Clock is 0.666 (1333mhz). DCTs is Unganged.

[richardjay]

I just changed the clock to 1066mhz but it still didn't work

[Vezina]

The memory controller is in the CPU.

Swap the CPU for another one and see if the issue persists.

If the issues is still there ,after the CPU replace ,RMA the motherboard or use only 2 memory slots for proper dual channel operation.
If after swaping the CPU the  issues goes away RMA the CPU.

[richardjay]

Thanks but the motherboard is too old to RMA - 3 years I think.

I have a feeling that I may have somehow damaged the memory slots when I swapped my old ram for the new ram.  Don't know how though 

[Vezina]

Thanks but the motherboard is too old to RMA - 3 years I think.

I have a feeling that I may have somehow damaged the memory slots when I swapped my old ram for the new ram.  Don't know how though  

You could use a magnifying glass and look into the RAM slot for bent pins inside it.

You can either use only 2 slots either change the motherboard for a newer AM3+ one , which is backwards compatible with the CPU.

Not many solutions available to get it fixed.

[richardjay]

Thanks - the machine does run with 3 sticks of RAM ... are you saying I shouldn't run it like that, as a last resort ?

[Vezina]

Thanks - the machine does run with 3 sticks of RAM ... are you saying I shouldn't run it like that, as a last resort ?

Running with 3 slots will drop the performance a little as the CPU memory controller will run in single channel mode ,this meaning that adding more ram may not. be the equivalent for more performance in your case .
AMD CPU-s give their best when used in dual channel and with 2 memory sticks.

But in any case as you are not able to run with 4 modules there is nothing more you can do ,except buying a new motherboard.
No  BIOS trick will make the defective slot to work again.