CPU and Motherboard upgrade for Premiere Elements 11

Hi all. Been perusing the Premiere Elements and Pro forums but still have a few questions.

I’m upgrading Premiere Elements from PrE9 to PrE11 and am upgrading some of my desktop’s hardware at the same time. I could use some advice about choosing a CPU, graphics card, and motherboard. The goal of this upgrade is to considerably speedup transcoding without breaking the bank. The budget’s a bit flexible but I’d like to keep it at or under $500 for the motherboard/CPU combo.

The computer will be used for editing and transcoding AVCHD videos. The videos are shot in either 1080i or 1080p using a Panasonic HDC-TM700.

I’m processing about 2-3 hours of video per week and my current system takes a long time to transcode. For example, it takes well over 3 hours to convert 1 hour of AVCHD video to wmv. An Intel Core 2 Quad Q8300 with 3 GB of RAM was fine for the occasional video, but it’s too slow for what’s currently needing to be processed.

New CPU:

At this point I’m looking at the following processors:

Questions:

1. ) Does PrE11 make use of hyper threading?
2. ) If PrE11 doesn’t use hyper threading is there much of anything to be gained by getting the i7? The i5 is about $90- $100 cheaper than the i7 CPUs and seems pretty quick.

New Motherboard:

I’ve had good luck overclocking Asus motherboards, so I’m leaning towards getting another one, but am open to alternatives.

The choice of board will depend mainly on Intel’s northbridge chip:

Ivy Bridge       –  Z77 chip

Sandy Bridge  –  Z68 chip

Question:

1. ) Are there any other northbridge chip/CPU combos I should be looking at?

Current Graphics Card:

nVidia Geforce 8400 GS 512 MB DDR2

Drivers are up to date and downloaded from nVidia.

Question:

1. ) Since PrE11 doesn’t use the graphics card’s GPU, will it be okay to continue using this card for the new build? I’m not a gamer and this card works just fine for the current build.

Additional hardware/software details:

PSU: Seasonic X660

HDD: Four 1TB 7200 rpm drives

Memory: 16 GB DDR3 RAM

OS: Win7 64 bit or Win8 64 bit (haven’t decided yet whether to go with Win 7 or 8)

Thanks in advance for your comments and help.