That is kinda dangerous, and today I made a less dangerous way on replacement mobo for the laptop :
The mod involves timed cutting of the IDSEL signal on the PCI connector to effectively hide the card from the system so BIOS will see nothing is present and lets you boot, but shortly after the timer runs out and enables the card again, and your OS will see it and can use it !
There's other methods that involve hacking the BIOS but I don't have a dump to check and seems nobody else has looked at it. I knew I could do the hardware way sooner and did

Anyway enjoy !