I would remove the HDD, and then see if it will boot to the BIOS. Assuming it does, then verify there are no other hardware issues. I'd also connect the HDD to another PC an verify no issues with it. Assuming the HDD checks out, I'd delete all partitions, reinstall the HDD in your G580 and try again. As far as deleting the existing partitions on the HDD, I prefer to wipe EVERYTHING, including the GUID Partition Table (GPT). I recommend using 'diskpart' from a C:\ Prompt, and running the 'Clean' command.
Lots of videos on YouTube, so not knowing exactly what you did, was this an attempt at a Clean Install of W11, or an 'In-Place Upgrade' from W10? Was your BIOS properly configured for W11; UEFI only, No CSM Support? What method was used to create the W11 Installation Media?
Personally, on a machine this old, I prefer to do a clean install of Windows 10 first, then perform an 'In-Place Upgrade to Windows 11. YMMV, but here's why...
Windows does a horrendous job with Drivers generally, but especially with W11 on old/unsupported hardware. In my experience performing a clean install of W11, Microsoft absolutely SUCKS when it comes to installing the correct drivers on unsupported hardware, often using 'Microsoft Drivers' where a driver provided by hardware manufacturer is basically a requirement for proper performance. They suck SO Bad, I've even seen 'Microsoft Drivers' with Driver Dates of 7/18/1968 and 1/1/1970 installed on Intel System Components!
As such, I prefer to start with clean install of Windows 10, set with up with 'I don't have Internet' and a 'Local Account', so NO Internet Connection! Next, 'Pause' Windows Updates, turn off ALL of the Microsoft Telemetry, and then install the Lenovo 'System Update' tool to install the correct drivers for your machine. Connect to the internet and run System Update a couple of times, as it usually doesn't get everything on the first run. Once your Drivers are all up to date, then run Windows Update. At this point, I will ‘Create an image of the partition(s) required to backup and restore Windows’ using Macrium Reflect.
Then it's on to Windows 11. I do an 'In-place Upgrade' to W11 (without a network/internet connection!), 'Pause' Windows Updates, turn off ALL of the Microsoft Telemetry, and then run the 'System Update' tool again...And again. Once that's complete, then I run Windows Update. Once everything is updated, I do another System Backup and ‘Create an image of the partition(s) required to backup and restore Windows’ using Macrium Reflect. Now there are two baseline images to fall back on should need options or have to reinstall if anything go south in the future.
This 'may' seem like extra work, but I assure you it works every time, and will prevent headaches. I've installed W11 on seven Lenovo PCs with unsupported hardware, and have encountered zero issues once I settled on this method. In the case of your Lenovo G580, getting the proper NVIDIA driver for your N13P-GL Graphics Chipset 'could' be a headache you avoid by using the Levovo System Update tool rather than relying on Windows. Hope this helps...
