PC won't POST after installing GPU

[ellen727]

So I've installed a RX580 2048SP and no display output. But when I take it off it POST just fine. I already enable legacy support if thats helpful and also updated the BIOS to the what I think the latest version. Any help would be appreciated..!!

[NonSequitur777 · Accepted solution]

@ellen727,

Welcome to our HP Community forum!

It sounds like you're on the right track with enabling legacy support and updating the BIOS. One common issue with the AMD Radeon RX 580 2048SP 4GB (or any RX 580 variant for that matter) is that it requires an 8-pin PCIe power cable directly from the power supply unit.

If this cable isn’t connected, the card will not initialize, and you’ll get no display output whatsoever -precisely the symptoms you're seeing.

Here are a few quick things to check:

1. Make sure an 8-pin PCIe power connector is plugged into the RX 580.

2. Confirm your PSU has enough wattage (An RX 580 requires a minimum 500-watt power supply).

3. Reseat the GPU in the PCIe slot and double-check connections.

4. If possible, try booting with your monitor connected to the motherboard's video output, go into BIOS, and set the primary display to PCIe (if available).

5. Disable Secure Boot and ensure CSM (Legacy Boot) is enabled -this often helps with older GPUs on newer UEFI BIOS systems.

Let me know how it goes -happy to assist further if needed!

Kind Regards,

NonSequitur777

[ellen727]

is 450W is enough?

[NonSequitur777]

@ellen727,

Well, 450-watt would be the absolute minimum wattage for an AMD Radeon RX 580 2048SP according to TechPowerUp: https://www.techpowerup.com/gpu-specs/radeon-rx-580-2048sp.c3321.

Kind Regards,

NonSequitur777

[ellen727]

The fan spun so that mean it receiving power right? but it'll spin for a couple second before stopping. Nothing is working so far.

[NonSequitur777]

@ellen727,

Does the 450-watt have an 8-pin PCIe power cable, and did you connect it to the card? Also, did you connect the card to your monitor?  If so, try a different video cable.

Does your PC work fine without the card?

Kind Regards,

NonSequitur777

[ellen727]

I got the GPU detected on Windows. But now it didnt output any signal unless I used the onboard one. Any idea how to disable the onboard graphics? I dont find it on the BIOS..

[ellen727]

I just realized that my HDMI to VGA adapter didn't work. Thanks for your help though.

[NonSequitur777]

@ellen727,

You're welcome, and good luck to you!

Kind Regards,

NonSequitur777