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In over 20+ years of using computers, I have always noticed that after some time from power on, the motherboard emits the usual single beep to say that everything is okay and the POST begins. This time clearly depends on the MB model, but usually is of a few seconds.

Now I have an ASUSTeK ROG STRIX X670E-E (BIOS Revision: 7.5) and what puzzles me is this time before the beep (and the POST) may vary a lot between power cycles.

It can be as short as 1-2 seconds, but also much longer, up to almost one minute. During this period, the screen shows nothing. After the single beep, as usual, the POST begins, and everything works fine.

I found this question, but it does not seem a dupe since in that case the time was always long. In my scenario, this happens from time to time only.

What can cause such a massive difference in power up time? What is the MB doing?

terdon
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Mark
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3 Answers3

22

DDR5 platforms like X670 have greatly increased memory training time compared to earlier generations, which occurs before POST. Because there is a much higher baseline error rate, it takes longer to converge on a set of parameters which guarantees acceptable signal integrity.

You may be able to control this with the "Memory Context Restore" option, which when enabled should have the memory controller reuse the results of the training run from last boot. However if random fluctuations have made it so that a reliable signal cannot be established with those previously derived parameters, then it will forcefully apply them, which would show up as memory instability.

matoro
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I had something similar on a refurbished Dell laptop I bought; I observed pre-POST delays in the range of 20-80 seconds (so always pretty long but sometimes very long). It also had some other weird behaviour. I updated the BIOS, to no avail.

I contacted the store's tech support, and they asked me to return it; they ended up replacing the motherboard. After that, the laptop has had a consistent ~5 sec pre-POST delay. So in my case, it looks like it was caused by a defect of some sort.

You could try updating the BIOS (if it's not already at the latest revision).

After that, if the motherboard is still under warranty, consider using the warranty. If the motherbord is old, try replacing the CMOS battery.

marcelm
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First of all, I cannot find your bios version here so I cannot tell if you have the latest. When a computer starts up, it will detect all connected devices, if a device takes longer to come back, that can postpone POST. You could strip your computer of all superfluous hardware and replicate the issue. Leave CPU and one RAM module, no hard drives, no SSD, no usb devices.

Note also, that depending on your graphics card, that also takes time to make itself available. I have noticed with newer more powerful graphics cards can delay POST even more.

Have you run a memtest ? If the firmware thinks the RAM is not in a good condition it will test memory.

You also should have a Fast Boot option in your BIOS to improve performance. You can also simply revert the BIOS to defaults to see if that improves things.

user2531336
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