Hello everyone,
I'm hoping to be able to help you improve your game performance with a few simple and not so simple steps. While the boost will vary depending on person. Please let me know in the comments if it helped.
List can be done in no particular order, or in an individual basis:
#1 - Run your anti-virus and Malwarebytes-Anti Malware to make sure you have no virus and malware on the PC.
#2 - Remove programs you have no intention of using. The less stuff clogging your hard drive the easier time it has reading data. Recommend you remove any program that says toolbar on its name as well. Bonus: Use Ccleaner for uninstalling programs, cleaning internet browsers, and finding out your computer specs.
#3 - Update your operating system! get all the latest update EXCEPT Microsoft Silverlight | Microsoft Essentials. While they won't have deep impact on the game performance I'm just saying they not as essential as they claim to be.
#4 - Update your graphic card drivers! This one has a increase in performance raging from 5% to 30%. For Nvidia use Gforce 326.80 if compatible with your PC. For AMD use 13.8 if compatible with your PC. They are both beta and came out this week, tuned to increase FFXIV performance. If you don't know what graphic card you using, Ccleaner tells you on the upper left corner.
#5 - Disable Windows Media Player Share Network. Is a feature almost no one uses and it eats up CPU pointlessly.
#6 - Remove as many possible programs from start up as you can without affecting the system. I personally disable them all except for the anti-virus. Go to run/search > msconfig > Start Up > Open task manager > Disable all none essential programs.
#7 - Lastly the most time consuming of them all and best left for last. Disk Defragment your hard drive. Warning: Do not Disk Defragment Solid State Drive (SSD).
I'll add more if I remember or if anyone suggest good ones. Hope this help someone, enjoy Final Fantasy XIV and hopefully much more clean/tuned PC.