G-skill Ripjaws V DDR4 4266 & Asrock z390 Taichi: cold boot training issues

[magellan]

I have 2x16GiB of Ripjaws V DDR4 4266 (G-skill part number: F4-4266C17D-32GVKB) running at 4009Mhz. on an Asrock Taichi z390 board that will pass literally hours of prime95 large FFT's and 6-core orthos 'blend stress CPU and RAM' as well as 12 hrs. of memtest86 yet sometimes will fail to train on a cold boot unless I manually reload my saved BIOS settings and initiate a warm boot (at which point it will always boot and pass the above tests). I've had to manually set the RTL Init and IOL Init values to 65 and 4 respectively otherwise the system won't train at all and I've been manually setting the ODT values for both channels (ODT WR, ODT NOM and ODT PARK) and most all the primary and secondary timings. There are still ~20 other values that must be being automagically initialized by the BIOS though, incl. IOL Offset, RFR Delay, tWRPRE, Write_Early_ODT, tAONPD, tXP, txpDLL, tPRPDEN, OREF_RI, tREFI_x9, tXSDLL, tXS_offset, tZQOPER, tMOD, ZQCS_period, tZQCS. Are any of these values particularly important to memory training? Are there any in particular I should be trying to tune? Does anyone have templates of working values for these settings at various frequencies?

Memory overclocking is definitely arcane if you don't have the right motherboard.

 

[EarthDog]

While you wait for detailed help (this stuff is deep in the minutia, those tertiary timings and functionality), be sure your BIOS is updated to the latest version if it isn't already. Old mobo, have you tried replacing the CMOS battery so maybe it pulls the timings that are 'there'? I don't know.

You shouldn't have to adjust anything to get it to boot again though.

Can you kindly update your signature so we know, exactly, what hardware you're working with?

 

[magellan]

The BIOS is updated to the last version. I don't have to adjust anything but I do have to reload the saved BIOS settings for the memory to train so I figure it must be one of the Auto settings in the BIOS that's giving me problems.
It's a 9700k @ 5.173 Ghz., z390 asrock Taichi and the G-skill 4266 2x16GiB DDR4 @ 4009Mhz (which is disappointing).
I may try just manually setting all the Auto settings to what is tested and works, instead of leaving it up to the roll of the BIOS dice to train it.
At one point I had it booting at 4111Mhz. on Auto settings, but on a cold boot it would never train again at 4111Mhz. I'm still hoping that by setting ODT, RTL Init and IOL Init I can get it stable at 4111Mhz. again, but I don't have the time for experimentation like that now.

 

[Woomack]

This is dual-rank Samsung B kit which is not even working at XMP on most best DDR4 motherboards. It's a matter of used IC. 4400 for this IC is like a hard wall on the best Z590 motherboards and the best IMC, assuming you had a lot of luck to the memory kit and motherboard. This is why you can't set much more than a 4000. On your motherboard you are lucky it even works like that.
On the QVL you can find 2 modules at 3800 and 2/4 at 3733. This is about guaranteed max.
ASRock Taichi isn't the best motherboard for RAM OC. It's not bad, but you can't expect it will train RAM much above you already set. You can leave everything at auto, set CL19-21-21 and VDIMM 1.5V, SA 1.5V, IO 1.35V and check how high it will boot. Then you will know if there is even a chance to set anything higher. 1.5V SA will be probably marked red. I don't recommend it to use it for longer, but it will be about max for IMC for a short test. If you don't feel comfortable with that then try 1.40-1.45V.

On the other hand, dual-rank Samsung B was causing problems at 4000+ with various motherboards or IMC. I had some kits that required higher voltages and more relaxed timings only to boot past 4000, while at 3600-3866 were working the same as other kits and could be stabilized at much tighter timings. Additional timings won't help with training/cold boot when RAM has problems to even boot one step higher. The supported 4266+ for the Taichi motherboard is for single-rank modules and this motherboard isn't even optimized for the latest DDR4 memory kits.

I would set 3733-3866 and try to stabilize something like CL14-14-14 or 14-15-15 as it has a higher chance to work than 4000+ at even XMP timings. It will be also faster.

 

[magellan]

@Woomack
I've read manually tuning ODT values can reduce required V-DIMM which is one of the reasons I began experimenting with that. Obviously it's capable of > 4000Mhz. because at one point I had it tested stable at 4111Mhz. but after a cold boot the Auto values just wouldn't work ever again. If I can get that frequency working that'll probably be the end of my experimentation with memory overclocking on this motherboard.
Whatever the BIOS code is that trains memory might be one of the key differences between a good memory overclocking motherboard and a bad one.

 

[Woomack]

It boots at ~4100, but as you see, the motherboard has problems with training. It can be because of RAM, motherboard, or IMC compatibility. I had similar problems with a couple of memory kits, like the Team Group DDR4-3600 CL16 kit with dual-rank Samsung B. It could work at 4133, but I had to set much higher voltages than should be required, only to make it boot at 4000+.
In your case, it's more likely that the motherboard just can't handle it. You can play with ODT, RTL/IOL, and other settings, but I can't help much with optimal settings, as on every setup, values are a bit different. In general, one step up or down from the auto, and check how it acts. Push some more when you see it reacting well. Typically I don't waste time on that as it only slightly helps, and even if you lower voltages or make it start at a slightly higher clock, then the motherboard still has cold boot problems.
All the Z370/390 motherboards were optimized for 3733+ with 8GB, single-rank modules. Higher Z490/590 were optimized for 3733+ dual-rank modules like you have.
There is a chance that earlier BIOS works better or there is a beta BIOS, as back then Nick Shih's team was digging some more in BIOS for OC records. I'm not sure if you find anything better.

 

[magellan]

How can you find out what the Auto settings are if the system won't boot at a given memory frequency?

The voltages I used when the Auto settings once worked at 4111Mhz. weren't really all that high either:

VCCIO 1.3
VCCSA 1.34
V-DIMM 1.48
Vcore 1.45

I tested this overnight w/memtest86 and over 7 hrs. of prime95 and orthos, it was on a cold boot that the Auto settings failed.

 

[magellan]

Wellllllll, it turns out I need a LOT more VCCIO and VCCSA to get these 16 GiB sticks stable at 4000Mhz: VCCIO 1.32V, VCCSA 1.37V (all these values are highlighted red in the BIOS settings, so I'm guessing they're too high?).

If I were to try for higher frequencies w/this kit and my Asrock z390 Taichi would I need even more VCCIO and VCCSA? How much might it take to get to say, 4100Mhz.?

 

[EarthDog]

How can you find out what the Auto settings are if the system won't boot at a given memory frequency?

Use a program called Taiphoon Burner. It reads all the details of the memory.

If I were to try for higher frequencies w/this kit and my Asrock z390 Taichi would I need even more VCCIO and VCCSA? How much might it take to get to say, 4100Mhz.?

Those are two of the voltages to play with, yes. Like was said, it's tough to tell what settings each thing needs. That's a lot for the platform and it is possible you've reached the end of the road. If you're benchmarking and trying for giggles, add a bit more SA/IO voltage and see if that helps stabilize things (along with DRAM voltage). But, you may have just hit a wall too...

 

[magellan]

Is it pretty much my motherboard that's holding me back? Or just a 9700k w/a lousy IMC? I see all sorts of incredible 32 GiB DDR4 overclocks w/9900k's at 4200, 4266, 4444. I've even seen an 8086k with 64GiB at 4173.

 

[Woomack]

You have a dual-rank Samsung kit. As I already said, this IC simply can't make more, and depending on the batch and some luck, it may get stuck at 4000, 4133, 4266, 4300, 4400 ... or boot up to 4500. You can have 2 of the same memory kits, one will work at 4133, and another one will make 4400.
You are not on the best generation for max RAM clocks. It wasn't even optimized for 16GB modules (on the BIOS side). People share various things on the web. Don't trust everything that others post ... especially when someone says it's fully stable. All those 4200+ results are a mix of good IMC, good RAM batch, and one of few good motherboards.
Intel's 8th gen has the same IMC as the 9th gen, with the exception of 9900k, which somehow has a stronger IMC. I had even better max clocks on the 8086k than on the 9700k/9900k, but typically 9900k is better. It's still random, but Intel used the best IMC in 9900k, and they typically run at 1-3 memory ratios higher than IMC in 9600K/9700K.
I would say that your results are typical for your CPU+mobo. ASUS Hero from that generation couldn't even work at more than 3866.

I have G.Skill Royal 4400 kit, which works at XMP only on 11700K+MSI Z590I Unify. It couldn't work at 4266+ on any other motherboard I was checking. This kit also has XMP 4400, and it can't overclock at all. In comparison, Hynix 2x16GB dual-rank could make 4600-4800, and 2x32GB could make 4200 on the same CPU+mobo.

 

[magellan]

It seems like most of the highest overclocking z390 and z370 systems I'm seeing are using 4x8 GiB, not 2x16GiB, so are the 4x8GiB rigs all using single rank DDR4?

I've even had more issues, I managed to lower my VCCIO and VCCSA and get more stability by changing my RTL init value to 66 from 65 while keeping IOL init at 4 -- with the exact same primary, secondary timings. The strange thing is when I was laboriously testing different RTL init values before an RTL init value of 66 for an IOL init of 4 wouldn't boot. I thought the Taichi series of Asrock 'boards was supposed to be their high end too.

 

[EarthDog]

. I thought the Taichi series of Asrock 'boards was supposed to be their high end too.

They are. But that doesn't mean every random setting will work.

 

[Woomack]

It seems like most of the highest overclocking z390 and z370 systems I'm seeing are using 4x8 GiB, not 2x16GiB, so are the 4x8GiB rigs all using single rank DDR4?

Samsung B are only 8GB = single rank, and 16GB = dual rank. 4x single-rank are easier for memory controller than 2x dual-rank, but not much. Most people were using 4x8GB only because it was easier and cheaper to buy good memory modules. Top overclocking motherboards used to be 2-slot. Right now it's not so obvious as some 4-slot DDR5 motherboards can make 8000 and some 2-slot are not optimized to run at more than 7000 (like ITX ASRock).

Taichi is ASRock high series, but not top. For some reason, there are no Aqua or OC Formula series with the latest chipsets. I assume that ASRock marketing and some other internal things have changed recently. They are clearly not pushing for the best results, but are releasing products for a mass sale. Their BIOS team is also the smallest from all popular brands, so they can't optimize all motherboards and they focus on those that need improvements or are top priority because of sales.