Can a smaller Firewire800 PCIE card replace another larger Firewire 800 Card?

Question

Unfortunately I found the headers on my computer's belkin 3-port Firewire 800 all tilted back somehow, and they snapped off when I tilted them forward to where they should be. As a quick fix, I have a smaller Firewire 800 card, but, it is not fitting for several reasons.

I am wondering: 1) why don't they fit 2) am I looking for another port 3) given that the new card has 2x firewire 800 and 1 x firewire 400, and the old one had 3 x firewire 800, how can the new card be so small, and occupy so few pins given the amt of data?

The first row on both cards have 11 gold pins, but they are different widths (the new one has smaller pins).

See below:

The original card has 4 total pin rows, of length 11, 32, 11, 32. The new one has 11 and 7. The original card only utilizes the first three rows, 11, 32, 11.

Answer 1

The 3 port card looks like a PCI card. The smaller card look like a PCI-e card.

PCI comes in several flavours:
* 32 bit wide and 64 bit wide.
* Running at 33Mhz or running at 66MHz.

This card looks like a run of the mill consumer PCI card which will run at 33Mhz and with 32 bit shared bandwidth on the bus. That means it can transfer at most 133MB/sec. (about the speed of a single gigabit NIC or slighty more than a maxed out single firewire-800 port).

The second card look like a PCI-e x1 card. Depending the version it can do 2.5gbit/sec per line (so 2½ as fast as the PCI card), 5Gbit per line (up to five times as fast) or even more if it is a hyper modern PCI-e v3 card. (though that would be useless since 1 lane from PCI-e v2 is already faster than three FireWire-800 ports).

In short: It is a totally different interface and it can be much faster despite using fewer pins.

[edit] Repeating what Techie007 already said in comments:
Please don't try to stick a PCI-e card into a classic PCI slot.