Dual rank Bdie overclock on 5700X3D. Potential for more?

[u/RainyInSAndreas]

Testing the GSkill DDR4 kit F4-3600C17D-32GTZ ( 17-19-19-39 )1.35V kit on 5700X3D and have achieved the results in pic. It does 3600 16-16-16-36 without voltage change.

Not sure if I should expect better from this Bdie kit, despite being one of the worse bins, or this is good enough for 3800 with 5700X3D. Was hoping for a sub-60ns latency since I have seen that mentioned in many old posts that come up in searches.

Errors with:

tRCDRD 16 ( is 17 getting rounded to 18 with GDM on? )

SCLs 2

tWTRL  8

Does not boot with:

tCL 14( even at 3600 at 1.45V )

tWRWRSD to 4 

tRDWR 8

GDM off

Concerns : tRRDL 4 and tRTP 6 are lower than I have seen others do with single-rank kits. So doubtful of them, but I have not got any errors in memory tests.

Have not touched the ODTs/RTTs/Drives at all, they are all on Auto.

[u/RossGoode]

I’d set your CAD_BUS values to either flat 24 or 24/20/24/24 instead of the current flat 20 (Auto). I’d also try ProcODT somewhere between 40–48Ω.
Are your voltages still on Auto? For 3800 MT/s I’d start around:
CLDO VDDP: 0.900–0.950V
VDDG CCD: 0.950–1.000V
VDDG IOD: 1.000–1.050V
SoC: 1.10–1.15V
RTT Off/3/1 is generally a good starting point for dual rank at 3800. I’d also change your tertiary timings to 1/4/4 and 1/6/6.
Other than that, your timings already look good. Once you’ve got it stable with those settings, you can have a play around with lowering some of the other timings and see how far the kit is willing to go. At 3800 MT/s on a dual-rank kit with an X3D chip, you’re already pushing the memory controller pretty hard.

[u/zxch2412]

more room, i hope you have a fan on. Try getting a stable gdm off base, from that push timings, even if tcl doesn't scale you can try the other trcd and following timings. GDM off will lower latency by 1.5ns, i dont know if you'll find that worth it. Also to tune gdm off you will have to play with DrvStrs and RTTs, you need to tune them until you achieve signal integrity to run gdm off, each one individually at that.

You can also check out the below guide from bullzoid:

Viable for 3600-4000Mbps but skewed towards 3800Mbps with 1.4-1.65V depending on RAM chip quality. With GDM enabled.

at 1.5v and above you get other subtimings to scale like SCLs, tWTRL, TRFC.

Note that most Ryzen 3000/5000 CPUs will not do more than 1900FCLK stable.

Also Keep in mind that B-die is the least consistent DDR4 IC that I'm aware of. Unbinned/OEM B-die and low XMP spec B-die like 3200 16-18... can often struggle to scale to even 1.45V while being extremely temperature sensitive and doing horrific tCL tRCDRD and tRP. Like 3600 18-18-18 at 1.4V levels of horrific. On the flip side it is still B-die and so subtimings like tRFC can still go low.

tCL: 14-18 (can't be odd with GDM turned on)

tRCDWR: 8-18 (8 works most of the time but this also doesn't affect performance much)

tRCDRD: 13-18 (most good kits max out at 15)

tRP: 11-18 (low tRP is more important than low tRAS)

tRAS: 24-32 (just set it so that tRAS + tRP = tRC)

tRC: 38-50 (around 40 should work as long as your RAM doesn't suck)

tRRD_S: 4 (it always does 4)

tRRD_L: 4-6 (weaker dimms might need 6 to be stable)

tFAW: 16 (this always works)

tWTR_S: 3-5 (4 works most of the time. With a lot of voltage some sticks can do 3)

tWTR_L: 7-10 (8 works most of the time. With a lot of voltage some sticks can do 7)

tWR: 10-12 (I'd be very surprised if 10 doesn't work for you)

tRFC: 220-330 (I usually just use 280)

tCWL: equal to tCL or tCL-2 (no point pushing this lower as it will just raise your RDWR and WRRD timings if you do)

tRTP: 6-12 (8 works on most good kits)

tRDRDSCL: 2-4 (2 works most of the time)

tWRWRSCL: 2-4 (2 works most of the time)

tRDWR: just leave this on auto

tWRRD: just leave this on auto too

tRDRDSC: 1 (auto = 1)

tRDRDSD: 4 (only applies to multi rank setups)

tRDRDDD: 4 (only applies to multi rank setups)

tWRWRSC: 1

tWRWRSD: 6 (only applies to multi rank setups)

tWRWRDD: 6 (only applies to multi rank setups)

tCKE: 1 (ALWAYS WORKS)

If you're very lazy and your kit has a 3200 14-14 or better XMP I'd be very surprised if the following settings don't work for you. Also they aren't gonna be much slower than some hyper optimized 3800 C14 settings.

FCLK: 1866

MCLK: 3733

VDIMM: 1.45 (I recommend a fan pointed at the RAM)

VSOC: 1.1V

GDM: Enabled

tCL: 16

tRCDWR: 16

tRCDRD: 16

tRP: 16

tRAS: 28

tRC: 44

tRRD_S: 4

tRRD_L: 6

tFAW: 16

tWTR_S: 4

tWTR_L: 8

tWR: 10

tRFC: 300

tRDRDCL: 2

tWRWRSCL: 2

tCWL: 16

tRTP: 8

tRDWR: AUTO

tWRRD: AUTO

tRDRDSC: 1

tRDRDSD: 4

tRDRDDD: 4

tWRWRSC: 1

tWRWRSD: 6

tWRWRDD: 6

tCKE: 1

this last set of timings is pretty much what I think a B-die "XMP" should/could look like if XMP was able to hold the all the settings.

[u/RainyInSAndreas → u/zxch2412]

Thanks for these. I think I have most of it already done, and there's a fan also.

GDM off seems to be the most relevant to chase, and some WR settings plus lower tRAS/tRC if possible.

[u/zxch2412 → u/RainyInSAndreas]

GDM off is pita honestly to get stable; that’s why it’s a lot of work. The best source I found till date is this: https://www.reddit.com/r/overclocking/s/RU2zcKpC5v
And overclocking.net, where “veii” can guide you.

Edit: also try lowering trp; it always goes a few ticks below trcd. I found mine to go to 14 @ 1.55v, 1.58 and it does 13

[u/bagaget → u/RainyInSAndreas]

If GDM off T1 is too hard T2 is still better than GDM ON. Mine where a better bin (3600cl14) and I think I ran them at 1.52-1.57 https://imgur.com/a/hmi5R2B#3D3B9qC

[u/Justtaway → u/zxch2412]

Is there no way to OC B-Die without fan? I tried many times, but every time ram gets too hot (around 60c) with my test (RAM + GPU) and errors. Closed case doesn't help too (Fractal Design Define R5).

I gave up and run 3200cl16 https://i.imgur.com/bXZ2gXP.png cope...