It's pci-e. If you want pci, I would go with one of the auzentechs. My xplosion cinema 7.1 should be in sometime next week. I'm going to try it out on my X540's and my pioneer/sony 5.1 home theatre via toslink.
There's a limited number on sale right now at ncix.
NCIX.com - Buy AuzenTech X-PLOSION Cinema 7.1 Sound Card DTS Connect Dolby Digital Live Sound Card PCI 32BIT - AZT-XPCINE In Canada.
There's also one for sale in the b/s/t forum. I would have bought it my self but already had one on the way.
Auzentech X-PLOSION PCI sound card