Loading screen extremly slow

Hi guys!

I've had a problem since the patch with the hunts (was it 2.3?) and I have no idea how to solve it.

When teleporting to a new zone I have 1-2 min loading time. If I teleport to mor dhona it could be even longer.
It takes around 1 minute to load the npc in mor dhona.
And today I decided to pick up pvp again, but it take around 30sec+ until I can see my enemies so sometimes I just die and I have no idea what just happened.

My sister has an older computer than me, but hers loads so much faster. She also has really slow connection so I don't think that is the problem since I use WTfast and got 110 mb/s.

What I have tried so far
WTfast
Cleaning up the computer (currently 500gb free space)
Cleaning up registry
Search the entire computer with Ad-aware
Defrag and scanned disk for problems
Redownloaded files through steam "validate files"
Downloaded a program called FFxiv priority booster
Changed priority manually to High but it changes back to low immediatly

The computer is rather fast when I play other games or do other stuff but FFXIV is the one I'm having problems with.

OS: Windows 7
Processor: Intel Core i5-3570k CPU @ 3,4Ghz (4CPUs)
Memory: 8192mb RAM
DirectX-version: DirectX 11
Graphics card: NVIDIA GeForce GTX 660


Is there anyone who could help me figure this out as I have nothing else to try but reinstall the entire computer, which I really don't want to do.

I want to bump this and hope someone has any advice what I should try next.
I want to play pvp but I can only play during 24 man pvp cause otherwise Ill just jump up to middle and die before I even can see the enemies.