I found an unopened Studio 7 Deluxe box, complete with the card and software. I'm trying to capture old VHS tapes, but my audio sync is about 2-3 seconds off.

 AMD 64 4000+ (Socket 939)

1gb DDR400

GeForce 8400GS

Running a clean install of XP Pro, all updated and drivers for everything up to date.

I'm getting the same problems in both v7 and 8SE. 

Also, I'm getting a garbled preview window. This did not occur on the P4 2.8, 256mb DDR333, Radeon 9600 machine I tried before, with the same results in the captured video.

Aside from capturing in short durations, what are my options? Is there another piece of (free) software that can capture from this card? Am I supposed to connect a floppy drive power connector directly to the card (manuals don't mention the connector, but it's on the board...)?

Yes there is. Try AMCapture.

Now, I am not familiar with Studio 7 and 8, but perhaps you can tell us what capture settings.  Other people who might have the same package as yours might be signing in the forums in a while.

In the meantime, welcome to the forum NayusDante.

Odd thing is, AMCap doesn't detect the card as a capture source. I also tried several other capture programs, but same problem.

At any rate, I found an alternative solution: A/V passthrough on my DV camera, capture through firewire.

What I'd REALLY like to know is what  that four-pin power connector is for, and if it would fry if I plugged a floppy drive power connector to it.