PC Turns on for 3 seconds, then off for 3-4 seconds and then ON again. No beeps

[Ryunosei]

Hello, as said on the title, everytime i turn ON my pc it stays on for 3 seconds then goes off for 3 seconds (motherboard leds are still on) and then ON.
My computer works perfect except for that.
I don't know if this is the correct section, but i think it might be related to motherboard maybe?
My setup:
PSU: [XFX XTR 650w](http://xfxforce.com/en-us/products/xtr-series-gold-full-modular/xtr-series-650w-psu-p1-650b-befx)
GPU: [Aorus Xtreme GTX 1060 6gb rev2.0](http://www.gigabyte.us/Graphics-Card/GV-N1060AORUS-X-6GD-rev-20#kf)
Motherboard: [Asus Tuf Z370-Pro Gaming](https://www.asus.com/Motherboards/TUF-Z370-PRO-GAMING/)
CPU: [i5-8400 4.0Ghz Coffee Lake 6 Core](https://ark.intel.com/products/126687/Intel-Core-i5-8400-Processor-9M-Cache-up-to-4_00-GHz)
RAM: [2x8gb 3200Mhz G.Skill TridentZ RGB](https://www.gskill.com/en/product/f4-3200c16d-16gtzr)
SSD: [250gb M.2 WD Blue](https://www.wdc.com/en-um/products/internal-ssd/wd-blue-ssd.html#WDS250G1B0B)
HD: [1tb Sata 3 WD Blue 7200rpm](https://www.wdc.com/products/internal-storage/wd-blue-pc-desktop-hard-drive.html)

 

[Calvin7]

Being an entry-level, the TUF Pro received many overclocking features in the UEFI BIOS, although not as many as those higher-end models such as the ROG series. CPU multiplier or ratio overclocking is available as well as BCLK overclocking.

3200MHz memory may be useful when if BCLK overclocking. Your CPU has a locked multiplier making multiplier overclocking out of the picture.

Not setting the memory and leaving it on [Auto] will result is speeds of 2133MHz which is too slow. Supported memory for Intel Core i5-8400 is DDR4-2666. Configuring that speed may give better results as well as setting DRAM Timings and DRAM voltage.

The on and off booting process is likely caused by not setting memory parameters and the BIOS is training the memory settings to find settings where it will run comfortably.

 

[Ryunosei]

thanks for the answer. I knew that from start and at first i had my memories at 2666 but 2 weeks ago i enabled XMP and now it's running at 3000. (my memories are 3000, i wrote it wrong on first post).

Should i turn off XMP?

 

[johnleonard]

your memory obviously supports the XMP otherwise you would have issues already so leave it on.
The TUF is a great board, almost took one myself after reading the reviews but have used Gigabyte for over 12 years and never a problem so stayed with what I know.
I had a similar issue a while back with my wifes PC booting to bios and then it looked like it had shut down but 3 or 4 seconds later it jumped straight into the full boot sequence and loaded normally.
A quick an easy way to see if it is the board or the system is try the following.
Enter the mscfg and then hide all windows settings. Everthing else simply turn off.
Try starting the PC again. If the issue is gone then it is something in your OS at start up that needs to be tracked down.
If the situation persists then it is 99% probability a bios setting
I tracked it down to an issue with the Bios settings. My wifes PC halted on boot and waited for the drives and then continued.
I have a setting in the Bios that has a timing setting. "Wait for Hard Disk" It was set at 2 seconds so I simply entered zero and now it boots normally or at least without any appearance of stopping.

 

[smorizio]

the issue is the ram to cpu speed cant be set at post. start with making sure the mb bios is up to date. if the auto speed settings dont set the ram right after the bios update. set it to default speed. if you turn on xmp profile and it does the same thing...use cpu-z read the memory xmp profile setting and copy them down and check with the ram vendor for the setting of the ram make sure they the same. go into the bios and set the ram setting yourself take the ram speed off auto. you may have to set the default ram voltage higher if needed for xmp speed.