Question Motherboard gives a constant VGA error and I can't boot into the BIOS or Windows ?

[Koen st]

My MSI MAG B550 Tomahawk gives me a cpu error for a few seconds and then gives a constant VGA error, this happens after I unplug the power cord. and to be honest I dont know what to do here, I have already updated the bios, tried to use an older GPU, gtx 1050, I have switched the CMOS battery. this is the second time I have had to fix this issue and I don't know what I did the first time to fix it, but when its fixed and I don't unplug the power cord it works fine and as it should. Could somebody help me and figure out how to fix this problem?

PC Specs
Mobo: MSI MAG B550 Tomahawk
RAM: 32GB DDR4-3200
CPU: Ryzen 5 5600X
GPU: AMD RX 6650 XT
(tested it also with my old GTX 1050)

 

[CountMike]

My MSI MAG B550 Tomahawk gives me a cpu error for a few seconds and then gives a constant VGA error, this happens after I unplug the power cord. and to be honest I dont know what to do here, I have already updated the bios, tried to use an older GPU, gtx 1050, I have switched the CMOS battery. this is the second time I have had to fix this issue and I don't know what I did the first time to fix it, but when its fixed and I don't unplug the power cord it works fine and as it should. Could somebody help me and figure out how to fix this problem?

PC Specs
Mobo: MSI MAG B550 Tomahawk
RAM: 32GB DDR4-3200
CPU: Ryzen 5 5600X
GPU: AMD RX 6650 XT
(tested it also with my old GTX 1050)

Which CPU ? BIOS version up to date?

 

[Koen st]

Which CPU ? BIOS version up to date?

my cpu is a Ryzen 5 5600x and the bios is the latest non beta, so yes

 

[Koen st]

UPDATE:

i have made it so that the pc will boot reliably with the gtx 1050, I dont know about the RX 6650 XT, im too afraid that it doesn't work, and I cant enter the BIOS or windows or the boot menu with the RX 6650 XT.

 

[COLGeek]

What is the make/model of your power supply (label on side of PSU has info)?

 

[Koen st]

it is an corsair cfx550m

What is the make/model of your power supply (label on side of PSU has info)?

 

[COLGeek]

it is an corsair cfx550m

Any idea how old it is?

When the 6650 XT was installed, did you connect the PCIe (6+2) connection from the PSU to it?

Also, double-check that both the required 8-pin and 24-pin power connectors on the motherboard are firmly attached.

 

[Koen st]

Any idea how old it is?

When the 6650 XT was installed, did you connect the PCIe (6+2) connection from the PSU to it?

Also, double-check that both the required 8-pin and 24-pin power connectors on the motherboard are firmly attached.

i have no idea how old it is, its my second pc and it is second hand, but I do know that the 6+2 connector is good and both the 8- and 24-pin are firmly attached to the motherboard

 

[COLGeek]

Sometimes there is a manufacturing date on the label of the PSU.

Have you tried the 6650 XT in another system?

 

[Koen st]

Sometimes there is a manufacturing date on the label of the PSU.

Have you tried the 6650 XT in another system?

i dont have another system to test with that I can use, so no

 

[COLGeek]

i dont have another system to test with that I can use, so no

Understood. Intent was to isolate the issue.

 

[DavidM012]

I asked a bot:

This issue—where unplugging the power cord (switching off the mains) on an MSI MAG B550 Tomahawk causes a brief CPU error and then a constant VGA error until “something” fixes it—is rare but does appear in enthusiast forums. It’s not typical behavior and isn’t widely documented as a known fault, but key patterns have emerged from other cases:

• The sequence of debug LEDs (CPU → then constant VGA) after a cold power cycle sometimes indicates a failed or incomplete device initialization—especially affecting GPU detection, even if the BIOS is updated and the GPU tested on other systems.tomshardware+1
• Reseating the GPU and cleaning the PCIe contacts have repeatedly resolved similar red VGA light problems for other MSI B550 Tomahawk users, especially after power cycles or hardware changes, suggesting a sensitive PCIe slot, minor contact issue, or static buildup.reddityoutube
• PSU behavior: In several cases, an aging or borderline PSU (power supply unit) with slow discharge or unstable power at start led to poor initial handshake between motherboard and GPU, especially after being fully unplugged. This could trigger “CPU” and then “VGA” errors until the system regained normal power sequencing.reddit+1
• CMOS battery and BIOS settings: Replacing the CMOS battery is worth trying—loss of BIOS settings due to a weak battery can lead to hardware initialization errors after power removal. Some have found switching to default or UEFI graphics options in BIOS or toggling CSM mode also helps.youtube
• Display connection protocol: Using DisplayPort with certain older GPUs has caused VGA LED errors during cold boot, usually solved by updating the GPU VBIOS firmware or ensuring the monitor is powered on before booting.reddit
• Deep resets necessary: In persistent cases, users have had to fully power down, unplug, remove CMOS battery for 5+ minutes, then reseat RAM and GPU to clear the boot issue.linustechtips

Best practice steps to try:

• Power down, unplug, discharge system (hold power button 15 seconds), reseat GPU and RAM, check PCIe and power cables for secure fit.youtubetomshardware+1
• Plug in, let board sit for a minute (some require time for supercap discharge), replace CMOS battery, then boot.
• Test with monitor ON before starting (especially for DisplayPort), try both HDMI and DP connections.reddit
• If available, test the GPU in another PCIe slot or another system again.
• If problem persists, try restoring BIOS defaults or toggling between UEFI/CSM boot modes.
• As a temporary workaround, avoid unplugging the main power if the system is stable when continuously powered.

These steps cover almost all variables that have resolved similar issues for others. If all else fails and the error continuously returns after power loss, consider that either the motherboard or PSU may have a latent fault with cold boot power conditioning—consulting MSI support or checking for warranty/recall notices may be necessary.tomshardware+2

The odd tie to power cycling suggests this is probably not a standard GPU or BIOS issue, but related to power delivery or initialization, with the B550 series occasionally sensitive to such resets.

Says it is a rare but not unheard of device initialization issue that's related to power delivery and since the corsair cfx550m isn't one of their finest units that's not a completely unreasonable assumption that the psu is declining with usage.

There isn't a wiggle it and it's fixed solution here just get a better psu in the end. It's rowing upstream to stay still so to speak - the least favorite upgrade but a quality unit that lasts 10 years is great value for money you only have to decide what size you want in case of future upgrades to avoid buying twice. an 850w unit could give you room for a nice bigger gpu if you're ever gonna go there. while a 650w unit will supply your mid range selections for years to come also.