Its way more than silver box with SSE4A, what is SSE4A? mmx+ is older & SSE4+ was out, yet this is another improved instruction set.

Also as report several months ago in theinquirer.org:Heres HOT Combo if you can afford it.
1-3870 & 1- 3870X2 with yesterdays released Crossfire X drivers make bios see two cards as Three & they come in near 18,000 in 3dmark '6 using VISTA ULTIMATE. Wow, OVER TOP. Again, if you can afford it.
drashek

1) No real "SSE4" support - just the AMD spin on SSE.

2) No HT. Remember Intel's next gen quad core beasts will have HT enabled which does help some work loads.

3) The rumour is this box is running at 1.6Ghz. Who knows if this is true, but if it is they have a long ways to ramp. Remember Intel has shown next-gen chips running well past 3Ghz *last year*.