b850 pro-a wifi No POST

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   b850 pro-a wifi asrock, doesn't POST, it shows red LED, sends power to mouse but not keyboard through USB. After a few seconds it flicks directly to green light and is stuck there.

Nu signal to monitor.
Tested without GPU card, only through cpu and internal graphics.

Tested by reseating ram modules, tested with just one module in different slots.

Removed battery for cmos reset.

I'm a bit lost on what the leds are trying to tell might be the problem with the way it acts. 

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ztilleto Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 17 Jul 2026 Location: Denmark Status: Offline Points: 60	Post Options Post Reply Quote ztilleto Report Post Thanks(0) Quote Reply Topic: b850 pro-a wifi No POST Posted: 17 Jul 2026 at 5:08pm
	b850 pro-a wifi asrock, doesn't POST, it shows red LED, sends power to mouse but not keyboard through USB. After a few seconds it flicks directly to green light and is stuck there. Nu signal to monitor. Tested without GPU card, only through cpu and internal graphics. Tested by reseating ram modules, tested with just one module in different slots. Removed battery for cmos reset. I'm a bit lost on what the leds are trying to tell might be the problem with the way it acts.

Xaltar Members Profile Send Private Message Find Members Posts Add to Buddy List Moderator Group Joined: 16 May 2015 Location: Europe Status: Online Points: 40653	Post Options Post Reply Quote Xaltar Report Post Thanks(0) Quote Reply Posted: 17 Jul 2026 at 6:12pm
	What are your full system specs? CPU: RAM: Power supply: GPU: Drive/s: What diagnostic lights come on when you power the system? There are 4 of them on the upper right corner of the board just above the 24pin power header. CPU, DRAM etc. A green light indicates that it completed power on self tests successfully for that particular component (CPU, RAM, Boot etc). Your RAM should be in slots A2 and B2 on the board. Make sure they are properly seated in the slots as they can be tight on new boards. Don't use too much force but enough to make sure they are fully inserted.


ztilleto Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 17 Jul 2026 Location: Denmark Status: Offline Points: 60	Post Options Post Reply Quote ztilleto Report Post Thanks(0) Quote Reply Posted: 9 hours 10 minutes ago at 8:23pm
	The problem is that it doesn't do the POST leds. That is the main thing that I would like to know if there is something that could cause it to just light first led and then just keep it for a bit and then directly to green. With no POST led progression for memory or vga, and it doesn't send GPU signal either through GPU board or internal cpu.

ztilleto Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 17 Jul 2026 Location: Denmark Status: Offline Points: 60	Post Options Post Reply Quote ztilleto Report Post Thanks(0) Quote Reply Posted: 8 hours 40 minutes ago at 8:53pm
	Cpu: AMD Ryzen 7 9800X3D 4.7 GHz 8-Core Processor Cooler:Deepcool LS720 SE 85.85 CFM Liquid CPU Cooler Motherboard: ASRock B850 Pro-A WiFi ATX AM5 Motherboard Memory: TEAMGROUP T-Create Expert 32 GB (2 x 16 GB) DDR5-6000 CL30 Memory SSD: Samsung 990 EVO Plus 1 TB M.2-2280 PCIe 5.0 X2 NVME Solid State Drive GPU: Gigabyte WINDFORCE OC SFF GeForce RTX 5070 12 GB Video Card PSU: Deepcool PN850M 850 W 80+ Gold Certified Fully Modular ATX Power Supply

Xaltar Members Profile Send Private Message Find Members Posts Add to Buddy List Moderator Group Joined: 16 May 2015 Location: Europe Status: Online Points: 40653	Post Options Post Reply Quote Xaltar Report Post Thanks(0) Quote Reply Posted: 5 hours 29 minutes ago at 12:04am
	Have you tried updating your BIOS using the BIOS flashback button on the board? Check page 53 of your user manual for instructions. If you don't have a physical copy you can find it here: https://download.asrock.com/Manual/B850%20Pro-A%20WiFi.pdf Page 57 of the PDF. Also make sure all your power connections are the correct ones. It is possible to accidentally use PCIe power cables in the CPU power headers. PCIe is 6+2 pins and CPU power is 4+4 pins, both 8 pins total but not the same pinout. If you still can't get the system to POST it may be worth disassembling it and connecting the board to the PSU with a single stick of RAM in slot A2 and the CPU/cooler installed. You will want to do this outside the case to rule out shorts under the motherboard. I typically rest the board on a mousepad or the box it came in. Use the display outputs from the board without a dedicated GPU. If you manage to get it to POST like this then add the second stick of RAM in slot B2 and test again. Then with each successful POST add the next component, SSD then GPU. Once it's all working outside the case, double check your case standoffs to make sure none are in the wrong place and causing shorts then reinstall everything inside the case and test again. Good luck.


ztilleto Members Profile Send Private Message Find Members Posts Add to Buddy List Newbie Joined: 17 Jul 2026 Location: Denmark Status: Offline Points: 60	Post Options Post Reply Quote ztilleto Report Post Thanks(0) Quote Reply Posted: 2 hours 46 minutes ago at 2:47am
	This happened after the system had been running for little over 9 months, died from one day to the other. I've not tried to do a cmos update, only done a reset. Had everything out besides ssd and cpu. But my question is also very much minded on how the leds behave. What can cause the leds to behave as they do and not do a prober POST sequence. I will try and take it all out of the case and redo a start install test.