I heard somewhere that you want to have your video card and tuner card as far apart physically from each other in the case as you can get them. I'm sure this is true to some extent, but is there a difference between 3- and 4-slot separation?

The reason I'm asking is that I need to add a network card. Should I add it in between the two cards or below the tuner? Adding it below would remove any possibility of interference from the network card (if there can be interference from a network card), but would increase interference due to the lessened distance between the other two cards. I have an nVidia GeForce4 MX 440 and a PVR-250.

In visual form, should I do this:

-Video
-Blank-
-Blank-
-Network
-Blank-
-Tuner

Or this:

-Video
-Blank-
-Blank-
-Blank-
-Tuner
-Network

Or does it even matter? Thanks.

I don't think it really matters. One reason for skipping slots in my experience stems from the inability of some boards (older boards so maybe this isn't an issue with the "smart" BIOSs of today) to properly share IRQs and the potential for conflicts with some cards under certain situations. For example, I ran into this on a board (I wanna say it was an old Intel 440BX chipset, but I can't remember for sure) a long time ago. The problem I was having was either with a SCSI card conflicting with a soundboard or something. The solution was to move one of the two to another PCI slot. Again, I don't know if this is much of an issue with a modern board.

The only other reason to skip slots I can think of at the moment is to minimize heat transfer between cards. In other words, if you have a card that generates a lot of heat (say a high clockrate video board), maybe it makes sense to isolate it from the other cards in the MB so it doesn't radiate heat to them. I don't know if this really matters at all, it's just one of the crazy thoughts running through my head as I sit here now at 2 AM with insomnia!

You know, the more I think about it, heat transfer would fall under the umbrella of EMR interference that you alluded to in your post, wouldn't it? After all, heat is simply EM radiation just as much as light is EM radiation. So maybe, theoretically anyway, you have a point about physical distance. Now does it really matter under real world applications? The easiest thing you can probably do is to test it as scientifically as possible.

Set the two in neighboring PCI slots, do some video capturing on various channels. Move them one slot apart and repeat the capturing on the same channels. Move them 2 slots apart and repeat, etc.

Now [somehow] analyze the resulting captured streams in a non-subjective fashion. I have no idea if there are standards for benchmarking video quality or how to measure them and compare samples. Perhaps you wanna look at the signal-to-noise ratio as an example. I thought I did it a while ago in cooledit pro with just an audio stream, you have to do a Fourier transform on the wav form and then there was a command that measured the SNR, I can't remember -- I don't know of any software that will measure it in a video/audio steam for you. Let us know if you come up with something or actually do some tests.

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Retired KM user (R4 - R6.04); friend to LH users.

I would do the first one, as the only real reason I know of to separate the cards is either irq conflicts (and I doubt you have that issue as slot1 and the last slot are generally bad about conflicting anyways), or heat.. Both video cards and video capture cards generate alot of heat, if you can help it you don't want any card in a slot directly next to either one. It generally doesn't hurt anything, but I have seen devices overheat when you get several hot pci cards crammed together with poor case ventilation.

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Have a question search the forum and have a look at the KnoppMythWiki.

Xsecrets

Thanks for the quick response, guys. I think I'll end up doing something like this:

-Video
-Blank-
-Blank-
-Network
-Tuner
-Blank-

It should be far enough apart for the cards, and it gives both the video card and the tuner a little more space for ventilation. Thanks again, I'll let you know how it works out.