Since I am not into Laptops with all their limitations, it was going to be a desktop PC with all the luxury of installing cards as needed.
I use an external audio interface with firewire 400 interface and had to find a suitable FW400 card for this.
As you may know, not many FW interfaces are known to work, particularly not those that use combo FW400/800 interfaces or combinations with USB. Here are two compatiblity lists, one from Focusrite and one from Presonus
Since not all of those interfaces are in current production or available easily, I had to choose a card by chipset. I chose the Startech 2 Port 1394a FireWire PCI Express Schnittstellenkarte, Product-ID: PEX1394A2V (Chipset Via - VT6315N) which is a two port FW400 interface with a native PCIe interface.
(...) the FireWire card also integrates a native PCIe single chipset design. With no secondary bridge chipset, your FireWire devices communicate quicker with your PC to ensure seamless operation of your connected peripherals.
(taken from the manufacturer´s product description)
The card is not in the lists but has the recommended chipset. It installed by P&P and works flawless with no dropouts.