Ubuntu – High temperature in a AMD Radeon HD4000/3000 series after upgrade

I was running 12.04 with Unity 3D for 6 months; my laptop ran almost silently and cool enough to hold on my lap with ~4 hours of battery life. I updated to 12.10 and switched to the Gnome 3 Shell. Now my computer gets too hot to hold on my lap, the fan is constantly running on full blast, and I have about 45 minutes of battery life. The behavior is consistent between battery power and A/C power. This is the output of sensors:

acpitz-virtual-0 
Adapter: Virtual device 
temp1:        +84.0°C  (crit = +99.0°C)

coretemp-isa-0000
Adapter: ISA adapter
Physical id 0:  +84.0°C  (high = +86.0°C, crit = +100.0°C) 
Core 0:         +74.0°C  (high = +86.0°C, crit = +100.0°C) 
Core 1:         +72.0°C  (high = +86.0°C, crit = +100.0°C) 
Core 2:         +75.0°C  (high = +86.0°C, crit = +100.0°C) 
Core 3:         +84.0°C  (high = +86.0°C, crit = +100.0°C)

radeon-pci-0100 
Adapter: PCI adapter 
temp1:        +76.0°C

I have an HP Pavilion dv6, Intel i7, AMD Radeon graphics. Please let me know if you need additional information.

What could be different between these two Ubuntu editions that caused such a drastic change?

Edit 1:

Per @Paul's suggestion, I ran htop to try to narrow down the problem. Here is the result!

(left side of terminal)

(right side of terminal)

This is about 10 minutes after boot-up, htop, yakuake, and a chrome page with 1 tab opened to this question are all that I have manually opened. The most taxing program to the CPU is htop itself. I think that the problem must lie elsewhere; my temps are already up to ~65C for the CPU and ~69C for the GPU, with nearly 0% CPU usage.

Edit 2:

As requested by @psusi, here is the output of 2 tabs from powertop (changed my colors for readability):

Again, all I am manually running is one google-chrome tab and a yakuake terminal. I am fairly new to powertop, so I am unsure how to interpret this. Let me know if you need info from the other tabs.

Edit 3:

I was having battery issues with 12.04 and fixed those by changing some lines in /etc/default/grub; credit this question.

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash acpi_osi=Linux acpi_backlight=vendor pcie_aspm=force i915.i915_enable_rc6=1 i915.lvds_downclock=1 i915.i915_enable_fbc=1"
GRUB_CMDLINE_LINUX="pcie_aspm=force"

I have kept these lines the same after updating to 12.10. Do these look OK?

Edit 4:

@Arup Roy Chowdhury mentioned that my AMD drivers might not be installed correctly. I am currently using the following driver (output from software-properties-gtk):

Should I be using a proprietary driver instead? The gnome-shell seems to be running graphics acceleration OK with the open source one.

Edit 5:

@hazrpg I have posted the log files you requested to Ubuntu Pastebin. Here is the dmesg.log, lspci.log, and lsusb.log. See any issues?

Edit 6:

@Sepero Here are my idle temps. I am only running one terminal ~10 minutes after bootup.

acpitz-virtual-0
Adapter: Virtual device
temp1:        +64.0°C  (crit = +99.0°C)

coretemp-isa-0000
Adapter: ISA adapter
Physical id 0:  +63.0°C  (high = +86.0°C, crit = +100.0°C)

Core 0:         +62.0°C  (high = +86.0°C, crit = +100.0°C)
Core 1:         +60.0°C  (high = +86.0°C, crit = +100.0°C)
Core 2:         +60.0°C  (high = +86.0°C, crit = +100.0°C)
Core 3:         +63.0°C  (high = +86.0°C, crit = +100.0°C)

radeon-pci-0100
Adapter: PCI adapter
temp1:        +68.0°C 

Just opening google-chrome to paste this edit for a minute has raised those temperatures by a few degrees each. My computer was not in the 60s prior to the update.

FIXED!!:

Problem solved. Thank you to @DrA7 and @YellowApple to pointing me in the direction of graphics card problems. I found this wonderful question and implemented @Nick Andrik's solution. In a nutshell, installing the proprietary drivers (fglrx-updates) from ppa:andrikos solved the problem. I can now use ATI Catalyst to choose my power mode and which graphics card (Intel or AMD) I want to use. My temperatures are down to ~44 degrees and battery life is up to ~4 hours again. I also installed Jupiter, which improved battery and temperatures further.

The open source drivers for AMD seem to be getting better, however it looks like their support for hybrid graphics cards (like mine) is not quite up to spec. Use the proprietary drivers for now.