Windows XP (any), Vista (any) or Windows 7 (any) 32 or 64 bit versions

Server versions of windows generally don't have required graphic card support installed

MAC-OS not supported (sorry)

Quad Core (or more) CPU Intel i7  930, 970,940,980X etc, Xeon X5670
i5 or core Duo processors will run, but be significantly slower on HD media

3GB or more as fast as possible for motherboard / processor combination used.

2GB Free hard-disk space
-HDR version only: 8GB Free Raid0 hard-disk system space to capture 3D

Must be NVidia, Fermi based design preferred eg:
GTX580, GTX480, GTX470, GTX480M, GTX590
Quadro 4000, 5000, 6000
also suitable but slower:
GTX260, GTX275 etc.
see list (but ignore ATI models) here
note: latest NVidia drivers must be installed

We prefer GTX cards made by PNY or ZOTAC : avoid MSI cards

Primary monitor can be as small as 1024 x 768
larger sizes to 1920 x 1080/1200 or above are preferable

can be same as the primary monitor or larger or smaller.

Alternatively can be 3D type in interlaced mode such as Zalman, JVC,
Hyundai passive 3D monitors.
 

For dual stream 3D, any pair or dual input car with WDM/DirectShow drivers
For multiplexed 3D ie Side-by-side, top bottom or interlace, then one input needed.

AJA Kona 3 (consult their site for DirectShow drivers)

Blackmagic decklink
Blackmagic decklink extreme 3D
Blackmagic decklink duo
Blackmagic decklink quad
Blackmagic intensity (HDMI input)
Blackmagic UltraStudio

Bluefish444 Epoch 2K Horizon

Deltacast

2 x IEEE Firewire can be used but 2nd port must be on second card/controller)

No specific CEL-SOFT recommendations, but check with capture card manufacturers' recommendations.

Check there are enough PCIe slots for the capture cards to be used bearing in mind the
GTX580 or Quadro graphics card occupies a double slot. ASUS GTX580 need 3 slots!