When i raid 0 i get a black screen

And you expect it to do what? Try to insert a bootable dvd or usb stick. It might boot from that, so you can install the os.

Never done Raid before but it doesn't look so difficult. I don't need it to boot the OS, I need it to get to the part were I press Ctrl+i and combine the two ssds. The problem is once I save the bios from AHCI to Raid it doesn't do anything, just black screen.

Ah, got the problem, but don't have a fast solution. Are both ssds connected to the Intel or ASMedia controller? Beside that: raid0 with ssds is worth nothing! It only increases the chance to loose your data by 100.

Put in the OS and saw that one the the disk wasn't partitioned. Do both of the ssds need to be partitioned? Also is it true about two ssds in Raid not performing good? I saw a video on youtube showing pretty good performance gains. Thanks for the advice.

First of all the partitioning might be the problem here. There should be now partition on the disks! Creating the raid0 will write a new boot record to the disks and so they will be empty after that anyway. You create the partition later while installing the os or initializing the volume in disk management.
Concerning the performance gains: you will see an increase of the transfer rates in benchmarks, but only in benchmarks. Unless you are frequently moving very large files (> 1GB) around, that doesn't matter for the real world. What matters is the very fast seek/search/access time, compared to hdds. And that stays the same in raid0 and even with sataIII. The downside of raid0: if your mobo or the raid driver or one of the ssds fails, you will never get your data back!