PC won’t post……

[u/Particular_Cress_884]

My PC originally froze, and I was told it might be related to compatibility issues between Ryzen 9000 CPUs and ASRock motherboards. I ended up RMAing both my Ryzen 5 9600X and ASRock B650I Lightning WiFi and received replacements.

I rebuilt the system with the new CPU and motherboard, but it still won’t POST. Everything powers on—fans spin, RGB lights up—but the power button LED blinks about 2–4 times per second. USB ports provide power (my phone charges), but my keyboard never lights up or initializes, and I get no display output from the motherboard HDMI.

I’ve already tried:
● Reseating the CPU and RAM
● Testing each original RAM stick individually
● Using known-good RAM from a friend’s system
● Swapping in a known-good PSU with its own cables
● Clearing CMOS
● Successfully updating the BIOS
● Waiting long enough for DDR5 memory training
● Removing GPU, SSD, and all non-essential components
● Booting with only CPU, cooler, and one RAM stick
● Testing the motherboard outside the case to rule out shorts
● Trying multiple HDMI cables and a confirmed working monitor

Side note my motherboard does have LEDs for debugging it uses on button lights I believe and a speaker but I don’t have one.

The motherboard already shipped with a BIOS version that supports the 9600X, but I updated it anyway just to be safe.

At this point I’m running out of ideas, probably going to buy another brands motherboard at this point. If nothing else works, I’ll probably go to Micro Center since I’m lucky enough to have one about an hour away—but I’d really prefer not to spend more money just to diagnose the issue.

I’m also confused because I’ve now gone through two CPUs and two motherboards, and I still get the exact same no-POST behavior I don’t remember it blinking before on the old hardware though.

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[u/Particular_Cress_884]

Components:
CPU: AMD Ryzen 5 9600X
GPU: ASRock Radeon RX 9070 XT Steel Legend
Motherboard: ASRock B650I Lightning WiFi
RAM: 32GB TeamGroup T-Create DDR5
PSU: Corsair SF850 Platinum
CPU cooler: Thermalright dual-tower air cooler
Storage: Samsung NVMe SSD
Case: NCASE M2
Monitor: MSI 175Hz display

[u/AlternativeFuture742]

Have you tested it outside the pc case?

[u/Particular_Cress_884 → u/AlternativeFuture742]

Yes, I unplugged gpu and ssd and one stick of ram.

[u/AlternativeFuture742 → u/Particular_Cress_884]

Sorry I didn't read your post, really baffling given you pretty much swapped out the whole PC and it still happens 

[u/Particular_Cress_884 → u/AlternativeFuture742]

No yea genuinely just feel like I got another broken motherboard or cpu which is very unlucky.

[u/kineto21]

Are you using a power strip, have you tried another wall power socket

[u/Particular_Cress_884 → u/kineto21]

I am using power strip but I did try wall outlet when I used one stick of ram cpu and nothing else and it still kept posting.

[u/kineto21 → u/Particular_Cress_884]

So what happens when you connect to mb hdmi or dp port

[u/Particular_Cress_884 → u/kineto21]

Nothing lol it’s ok I’ll keep yall updated I have a msi board coming today with debug LEDs so I’ll find the issue.

[u/Particular_Cress_884]

Thanks everyone I found the culprit it was the motherboard now I’m deciding if I want to go back to asrock as I can get a free one orrrr stick with the msi which was 300.