CPU: 1700x

RAM: Corsair Dominator CMD16GX4M2B3000C15 (it is on the qvl list) 

Issue:  When restarting, the computer will sometimes boot loop 1-5 times before turning on.  Once on, the computer performs flawlessly, and without issue. 

It seems to be tied to the XMP profile on my RAM.  When set to the advertised speed of 3000mhz (board drops it down to 2933) is the only time I have observed the issue happening.   If I drop the RAM down to 2666 it seems to boot just fine.  

There is an overclock on the CPU, but the issue persists regardless of the overclock being there or not.  I have also tried adjusting the SOC voltage, and the RAM voltage slightly.  It seems to happen less with that upped slightly, but it still occurs. 

I have ran Memtest86 overnight without error as well, so I do not think the RAM is having any issues. 

I know there isn't a huge difference between 2666 and 2933.  But I also feel like having paid so much for this board and the RAM, that it should work as expected. I reached out to ASrock through their other support channel, but the advice given to me was to return the MOBO and RAM...

Any other suggestions?  I'm willing to wait if it's a bios issue that can be resolved.

Thanks!

I have tried having it both on and off and it made no discernible difference in the boot loop issue :( 

*EDIT* What is the "boot training' option anyway?

Auto = On

If I disable it i get the 5 times beep bootlop too (3200 memory).

It's not always a "cold boot" either.  Normally I'm just restarting to install updates or do some troubleshooting. 

I would say on average it only cycles once or twice, but can go up to 5 times.

When it cycles once or twice, I check RAM speed in CPUZ and it is 2933

Sometimes it doesn't boot loop at all and works right.  I won't change anything, and then the next time I restart it will boot loop 1 or 2 times. 

Timings are set by XMP, or when to match XMP when I do it manually.  I believe they are 15-17-17-35, voltage gets automatically set to 1.35 I believe, and I have tried as high as 1.4 to temporarily test. 

Thanks!

I've noticed what I believe to be the same issue on my X370 FPG (basically the same chipset). I'm not sure if it has always been there and I just wasn't paying attention, but it sounds like it's trying to start up, and then the fans quiet down, and then it ramps up again and starts as expected. So I can't be sure, but I believe it is failing once, as you have described you are occasionally experiencing.

I don't have any tips for addressing it, because if I am correct and it is failing, it's only failing once.. So I'm not that worried about it (yet).

It basically kicks the fans on, then turns off, then kicks the fan's on, and then turns them off. The debug LED stops at "F9."  Doesn't happen everytime, can happen as little as once, and as many as 5 times.

I've been trying to work with Asrock support via email, but it's kind of been a joke :(.  They're advice is to take the MOBO back.  But I have a feeling a new MOBO isn't going to fix it. ...

I agree. I wouldn't return your board. If you're worried that it's going to brick the board, dial the memory back a bit until the next microcode is incorporated into your UEFI. Wash, rinse, repeat until everything runs the way you want it to.

Your situation has be thinking maybe I should dial my memory back, just to stay on the safe side..

I'm not really afraid it's going to brick the board or anything.  It's just annoying, especially because this board takes quite a bit longer than my previous ASrock Z77 board to turn on anyway.  Then add the fact that it has to restart several times before turning on.  

I'll probably just deal with it, or like you said, turn down the memory a bit.  It's a whole new architecture, so some hiccups are to be expected.  I just wish the Asrock tech support was better.  It would give me more confidence in waiting.  

I contacted their support and got a very nothing answer, "Update to the latest BIOS or fill out an RMA". Took them like a week to respond, too. There I was, expecting some *fantastic* answer from "the best" manufacturers around, and I was left feeling much differently than I did.

Another time I called ASUS support about a graphics card I purchased at a Best Buy, and the rep was combative, unhelpful, and seemed genuinely disinterested in talking to me. I was coming from a graphics card made by Sapphire that had "FLeX" technology that enabled 4 displays out of the same card, and when questioning the rep about why the ASUS card I had just purchased wasn't able to do the same thing, he assumed I had "hacked" the card I was referencing into making it work the way that it did.

About the only customer service people I have ever had a good time talking with are the people at GoDaddy, Microsoft (Office365), and some of the people at Sprint. Everywhere else is a total crapshoot.

Logitech and Corsair have been pretty top notch to me.  Corsair can be a little slow sometimes though.  

1.  I hadn't yet installed the drivers from Asrocks's website.  Specifically, the All-in-one driver immediately fixed the issue.  It appears to affect how the UEFI sets the XMP settings for RAM.  Before installing these drivers, no matter what I set the RAM would reset itself to the lowest speed setting and I would go into the 4x reboot loop (maybe some kind of safety feature?).  So if you haven't done it yet...install this!

2.  I tried the RAM (same Dominator RAM that you are using) at a number of settings.  it seemed to work fine until I set it to anything faster than 2666 MHz.  At that point it reengages the reboot loop and when windows does finally start, the RAM runs at the lowest speed.  So for me...2933 and up is out of the picture for now with 2666 MHz being my top speed.  

Hopefully a future update to the BIOS will allow us to run our RAM at full speed.