Be interesting to see if anyone really knows anything on this, I suspect not to be honest.

If it's a v1 especially, it may degrade your overall VGA experience if you are using pass thru. Even a v2 may degrade what you see above 1024x768. Apparently may make it a bit more blurry than without such cards. Not sure I ever noticed it but even on a 21" screen I tend to use 1024x768.

There's also the question of whether the Voodoos may overheat on faster boxes anyway (was some debate on here - I think my v2s were OK with a p4 2.8ghz but a PCI v3 overheated in a socket a board).

Personally I keep my main rig free of retro stuff (other than emulators) so it doesn't lead to compromises - eg older directs versions, sound issues (never mind dos, just a3d and eax). In other word, if you have the room I'd have a second machine (or three) for old games.

I noticed no blur in a 1600x1200 resolution, when using a Voodoo2 VGA out.

Well, you have some awesome DAC with the host card then. I get slight blur on even 640x480 using the passthrough cable.

Screen moire [those moving 'wave' patterns you see especially on black or solid color back gounds] can also be an issue with either the pass-thru cable or KVM cables if you use those. I recently upgraded my KVM switch and image quality improved noticeably on both my V1 and V2sli rigs, which was nice to see.

To the OP's main question, I don't have an answer. But I'm curious as well since I'm thinking of experimenting above a P4-2.8 on my V5 rig, though I think the V5 might be safe.

Thanks for the replies. I am thinking that a card sitting idle in its slot is not likely to impact on its lifespan, since the card would not be drawing any current. The only issue may be the powering down and up of the card. That being said, AFAIK the pci slot is powered even when the PC is in standby mode.

I have read that the voodoo cards do scale with cpu, and that the voodoo 2, and to a lesser extent the 3, have a bug by which they overheat when combined with a CPU that feeds them data at a faster rate than what was intended at the time of their design, despite the bottleneck imposed by the cards running at a maximum of 66mhz, which btw applies to both agp and pci varieties. I have also read reports of cards running fine in modern cpu setups. Ultimately one needs to check temps of their card on first go to ensure the card does not burn out (it happens VERY quickly apparently).

Not by much at all if you keep them cool, if they are sitting like 80c all the time they will surly fail but if kept in the 50s or 60s then they should last much longer than you would care to have them. Second the thick oxide gate (transistor level) is so much thicker than anything used now days so in theory these cards if maintained could last for decades till the memory or mosfets kick the bucket.

For V1 and V2 any stick on heatsink and a single 80mm fan nearby is enough to keep them cool long term. V3 and V5 you need something better but it does not take much to maintain them.