How Do I Tell Which Soundcard Don't Use CPU Resources?

I am researching sound cards and cannot tell which cards do all the sound processing on board and which delegate CPU resources to the task. I am looking to spend eighty to a buck fifty. I tentatively I am going to go PCI as I have learned that PCIe cards are mainly for people that don't have a PCI slot as sound cards don't use all the available bandwidth on PCI and PCIe cards have a PCIe to PCI bridge. I don't play games not even on my new PS3 I listen to CD & online music and online videos, if I get a PC BD-+RW it will not be to watch BD movies but to store large amounts of data on disk.

Was looking at the HT Omega Striker 7.1, out of 329 eggs it had 243 Excellent, 54 good, 17 average, 6 poor, 9 very poor but it seems that it may not work with Windows 7.
Other PCI card that I am looking at are

ASUS Xonar HDAV1.3 Slim
AUZENTECH AZT XPCINE 7.1
ASUS Xonar DX 7.1

PCIE cards are ASUS Xonar D2X
Creative Sound Blaster X-Fi Titanium Fatal1ty Professional

Anyone have any thought on these cards? How about other cards?

* GIGABYTE GA-EX58-UD4P
* Intel Core i7 920 Nehalem 2.66GHz
* Crucial Ballistix 3GB (3 x 1GB) 240-Pin DDR3
* MSI R4670-2D1G/D3 Radeon HD 4670 1GB
* Western Digital Caviar Blue 80GB 7200 RPM SATA 3.0Gb/s 3.5
* Windows 7 build 7100