Linux/Ubuntu custom refresh rate

[gorio]

I have old Flatron W2442PA 1920x1080 60hz
On Windows it was able to run 1920x1080 75hz using CRU or Radeon software.
On Linux there are xrandr and cvt to make it possible... but it does not do the trick, most likely because reduced blanking is not supported by cvt utility and it cause frequency exceeds it's cap.
After digging more I found about umc which can calculate timings with reduced blanking but since I am Linux noob I can't run it.

So my question is how I can calculate this modeline or how to translate timings from CRU/Radeon?
My working timings in CRU and Radeon software
http://i.piccy.info/i9/980e0e5107a94e060...imings.png
and modeline generated by cvt (which does not work)
"1920x1080_75.00" 220.75 1920 2064 2264 2608 1080 1083 1088 1130 -hsync +vsync

What I can understand it's 220.75 is pixel clock and it's too high, cru and radeon calculate it as ~164.6; 1920 and 1080 also easy; but +/- sync seams to be out of place and other 6 numbers I'm not sure.