Sabertooth 990fx memory and post trouble

[Katman]

I am building a 990fx with a fx-8120.

I had hyper x memory that ran fine without oc.
I did the auto oc and got 3.8 1666.
9-9-9-27 @1.65

Some cores would fail when running prime.


Now I am trying corsair vengence.
9-9-9-24 @1.50

With no oc it runs fine.
The auto oc fails and hangs on VGA_LED.

Have tried 2 video cards both slots
the sabertooth and a 990x evo.

Manual oc works for a while but then
POST error on VGA_LED after reboot.

5 hours prime at 3.8 1666 no errors
but then it won't reboot. VGA_LED.

Working on 3.7-3.8 tring 1646 and 1628
but both have failed to reboot after running prime.

I am new to AMD and not sure what I am missing?

Is it a bios setting or is this memory bad?

Have oced 2 other asus with intel cpus and no trouble
and have oced evga x58 with no problems also.

Thanks.

[HiVizMan]

Sounds like your ram is unstable. Have a look at the voltages and settings your are changing in the BIOS to overclock your ram.

[Katman]

It's annoying that a mem problem will hang on the VGA_LED.

At 1646 It would still hang after reboot
after 1 hour running prime.

Now I am trying it with the mem at 1626 again
with the 41 and 2t timings added.

So far so good. 3.7 is fine with me.

I am getting 7.7 7.7 7.4 7.4 7.7 on WEI.

The mem is only getting 1400 on passmark, is that an AMD thing?

Also 40 c max after a couple hours of prime alright for AMD?

Thanks.