Understanding FPS - GeoVision GV-650B vs GeoVision GV-800B

This is my first post on this forum though I have perused for quite a while... great info here!

A friend of mine wants a PC based CCTV system with 12 cameras, 6 outdoor, 6 indoor.

I am looking at two distinct Geovision 16ch cards, the GV-650 and GV-800. Regarding the FPS, the 650 is rated at 60 FPS (record rate) and the 800 is rated at 120 FPS.

First Question:

Since I am not using all the channels, will the FPS still be divvied up evenly between all the channels, or would the max be divided only according to the cameras that are recording (If I choose to do round the clock and not motion, just theoretically).

For instance, would I get 60/16 - 3.75 fps with only 12 cameras plugged in, or get 60/12 = 5. Also, both these cards feature something called "Adjustable Camera Framerate"... So will dropping the FPS on one camera allow me to raise it on another?

Second Question:

For the PC, what type of specs would I need for it to run well and what should I consider while looking for a cost effective build? Do I need a discrete video card? How about RAM wise? Processor wise?

Thanks in advance for the help folks.

I designed chip sets for these applications. As I can not identify the chipsets on their boards, my answer could be wrong.

PCI Bus allows 120 fps as Max bandwidth for D1 sized NTSC video. So 4 Channels of each 30 FPS can be recorded and displayed.

PCI -E bus(Lane 1) allows 240 fps for D1 X NTSC, almost double to that of PCI bus.

As to PCI -E (single lane), 240 FPS for 8 Channels of D1 sized video,

But not for 16 Channels of D1 sized video.

Theoretically PCI -E allows 160 FPS of 16 Channels of D1 sized video, that is, 10 FPS each for D1 sized NTSC video.

But I noted that they state 60 fps in total, so it could mean 5 FPS for 12 cameras. So your calculation could be right. I do not understand why they would give only 60 FPS???. You may need to buy 2 cards for better displaying rate, as pci-e bus provides independent bandwidth each card.

The recording rate could depend on the video frame rate delivered to PC and its pc spec, because its CPU handles compression of video data. You may follow their minimum guide line. But higher spec is much better for stable operation.

Can you tell me how much you pay for those cards?