Should I crossfire my 4870?

No need but, I personally love scoring almost 20,000 points in 3dmark06 with max resolution, max AA, max everything

You wouldn't ask if you wouldn't want it, so yes crossfire if you want to play all max.Or, for better feeling, sell this and buy 4870x2, it's just sooOOO HOOOoot!

And i7 will scale incredibly good with crossfire or dual gpu card.

Benchmarking isn't my thing, I am more into practical use than a general score since 3dmark no longer accurately display performance of cards in games and 3D environments.

Do you think a 4870 can get games at max setting excludes AA and AF (<-not that demanding right?) on 1920x1200 with avg higher than 40? Another factor holding me from going multi GPU is spacing, it seems most mobo manufacturer expect everyone either uses on board sound chip or a PCI-E sound card. I have a PCI X-fi (first gen) sound card and I find it every difficult to fit in a system with multi GPU or Aftermarket heatsink.

I am planning to get an Asus P6T Deluxe. With a sound card blocking the upper card's fan I would expect temp go skyrocket. Also I am not a big fan of stock cool due to its piercing volume when the fans are actually working, trying to fit 2 cards with aftermarket cooler is near impossible (T-Rad2?), let alone jamming another sound card in between.

What's the advantage of getting a 4870x2 over 4870 cf? besides the obvious "saving space". And again 4870x2 without aftermarket cooler option means heat and noises. Does 4870 cf adds up the vram to a net of 1gb vram?