[citation][nom]frombehind[/nom]say hello to "20min" battery life =(They gotta "scale down" mobile form factors with weaker chips that barely sip power insted of drinking it wholesale. It really is a tradeoff untill they make a seroius breakthough in batteries.[/citation]
The iPad 3 has a 42.5 Watt-hour battery. With the A5X chip, it gets 6-10 hours battery. My 11.6" Acer netbook has a 47 Watt-hour battery, and gets about 6-7.5 hours battery, which utilizes an AMD Fusion C-60 APU. An x86 isn't going to mean 20 min battery. With a rough calculation (assuming 6 hour battery-life), my unit drains ~8 watts per hour, which includes screen, wifi, CPU, GPU, and chipset. in a "normal" tablet unit (say, an iPad 2, which uses a 25W-hr battery), that would translate to about 3 hours battery, assuming the same 8 watt drain. Obviously down-scaling the screen, motherboard, using low-voltage RAM, and utilizing a more efficient x86 CPU, such as AMD's Z-01 APU (5.9W TDP vs the C-60's 9W TDP) will decrease power draw, so it would look more like 5 hours battery, vs 7. While a significant difference, it's still do-able. Also keep in mind, this is all on the aging 40nm fabrication process. 28nm is the norm, which will further decrease power draw.