Quote Originally Posted by danielkza View Post
I made some small progress. I found out that a tRCD of nine with a CAS Write Latency of 8 over DDR3-1600 causes the reboot cycles. Chaning tCWL to 9 instead causes a hang with the DRAM LED lit up. The other subtimings don't make any difference at all: I relaxed CAS Write Latency, Write Recovery Time and Read to Pre Time up to 12, and DRAM RTL up to 40, and nothing changed. The funny thing is with a tRCD of 10, CAS Write Latency of 9 and above also causes the hang. Maybe it's my RAM after all?

Here are the subtimings set by the board, with XMP and 2133 9-10-9-28, respectively.
Code:
* Primary Timings *
DRAM CAS# Latency:       7
DRAM RAS# to CAS# Delay: 8
DRAM RAS# PRE Time:      7
DRAM RAS# ACT Time:      24
DRAM COMMAND Mode:       2

* Secondary Timings *
DRAM RAS# to RAS# Delay:      5
DRAM REF Cycle Time:          88
DRAM Refresh Interval:        6240
DRAM Write Recovery Time:     10
DRAM READ to PRE Time:        6
DRAM FOUR ACT WIN Time:       24
DRAM WRITE to READ Delay:     6
DRAM CKE Minimum pulse width: 4 
DRAM CAS# Write Latency:      7
DRAM RTL(CHA):                D0: 32, D1: 33
DRAM RTL(CHB):                D0: 32, D1: 34
Code:
* Primary Timings *
DRAM CAS# Latency:       9
DRAM RAS# to CAS# Delay: 10
DRAM RAS# PRE Time:      9
DRAM RAS# ACT Time:      28
DRAM COMMAND Mode:       2

* Secondary Timings *
DRAM RAS# to RAS# Delay:      7
DRAM REF Cycle Time:          118
DRAM Refresh Interval:        8139
DRAM Write Recovery Time:     10
DRAM READ to PRE Time:        9
DRAM FOUR ACT WIN Time:       33
DRAM WRITE to READ Delay:     9
DRAM CKE Minimum pulse width: 6 
DRAM CAS# Write Latency:      8
DRAM RTL(CHA):                D0: 32, D1: 39
DRAM RTL(CHB):                D0: 32, D1: 40

What slots are you using??

At DDR3-2133 you'd definitely need a tWR of 12. Can you get the DRAM 100% stable at any frequency timing combo? What's it like at DDR3-1333 with 7-8-7-20 2N timings (super slack I know)? Just want to see where it's stable and where it falls over.

Also, can you list your third set of timings please?

-Raja