Help: Gigabyte GA-7DXR and 3 DIMMS - exteremely unstable.

[funks]

Hello,

I'm having a problem with my new GA-7DXR and 3 DDR DIMMS installed.. (The dimms are Crucial 2100 2.5 NS)..

I know that the mem chips works fine as I've ran them by themselves and they work great..

I do know it's none of the slots as i've tried different slots (different combinations) and the mainboard is stable as long as I don't use all three dimm slots (2 is okay)..

I tried the latest BIOS (F4) to no availe..

Is anybody out there using a GA-7DXR with all DIMM slots fully populated? Any problems?

Instability as in if I try to boot my system with all three slots filled, win2000 locks up with blue screens.. Even win2000 install fails..

If I just use two dimm slots (any combination), system is very stable..

Funks..

 

[funks]

It's not a heas issue as I have a nice ANTEC case with 5 case fans and the temps are normal (43c for the CPU, 28 for the mobo).. Nor is it a RAM issue (i've tested all three by themselves, not one lockup)..

These are PC2100 2.5 NS 256 MB DDR DIMMS (NON ECC)..

 

[funks]

Oh welps, it seems that one needs REGISTERED DDR RAM if one is gonna use all three slots..

 

[MrCoyote]

This does not sound good at all. I was thinking on buying this board, because of the 3rd slot for future expandibility. But I bought 2x256 Crucial unbuffered DIMMs. Does it say anything in the 7DXR manual about using registered dimms?

 

[oldclocker]

It sounds like a BIOS settings issue ... specifically memory timings. I habe bought the board, but have not installed it yet. Look at the GIGABYTE forum on AMDMB for more pertinant information.

 

[funks]

The AMD760 docs state that for less than 2 or less dimms, it's okay to use unbuffered.. But 3+ requires buffered dimms (registered)..

 

[Tummy]

Do all 3 have to be registered, or just the one in the 3rd slot?

 

[GundamF91]

1st slot is DIMM0, while 2nd and 3rd share DIMM1, so I think you need at least 2 registered at 2,3 to get them to synch right.

damn, I can't believe they still haven't sorted out 3 DDR timing issues. I had no plans to use more than 2 DIMM, so I picked 8K7A...now it seems even more reasonable of an option.

 

[Bingo13]

All three need to be registered to adhere to the AMD760 specs. I can get fairly normal operation with all three slot full with non-ecc/registered memory but it requires the slowest settings and it still flakes out at times. I just ordered three sticks of registered memory as I really like the board after playing with it for a day. However, the registered memory does not overclock at well due to the timing differences. It will be interesting to see how the Abit KG7 operates with all four dimms full.

 

[Gandu]

I heard the same, if all three are populated then CAS will rise to 3

 

[Gandu]

I just read the same about Abit KG7, here is what Abit has to say about it:

Memory
1. Four 184-pin DIMM sockets support PC1600/PC2100 DDR SDRAM module
( 2 unbuffered and 4 Registered DIMM )
2. Supports up to 4 GB MAX. ( 64, 128, 256, 512,1024 MB DDR SDRAM)


Read more about it at: http://www.abit.com.tw/english/product/motherboards/kg7.htm

Does it give us another reason to wait for another chipset/board tha will get rid of that AMD 760 Chipset barrier?

 

[GundamF91]

might have to wait abit longer. I dont think they can solve it so fast. might as well wait for a Palomino with 166/333 FSB later on.