@Marcin-Debowski Yes baseline at 3.3V. I use a common bench power supply that has a variable volts output and displays the current drawn, in amps. I believe you have a similar power supply? I have my supply set to 3.3- 3.4V and the amp meter nicely displays the current required at that particular moment of the Omega boot, etc. Not a graph providing setup, but useful and accurate.
I just reread this thread. It is about various problems users had powering their Omegas, including your posts about tests with small Chinese made power supply boards. You mentioned powering an Omega with 5 volts. By accident I did that once with a bare Omega for an hour or more. It ran fine, but got quite hot. After that it always required at least 3.4v to boot completely and now it draws more current ... I believe the 5 volts changed or degraded something in that Omega.
What confuses me is your statement "recalculated from 7.0V to 3.3V". What did you do here? Did you calculate the amps at 3.3V by Ohm' Law for a constant load: A = 7/3.3 x (current measured at 7v) ?
To check your setup you could run this test - in place of the Omega wire a known resistive load, say 80 ohm 1/4 watt resistor or 16-20 ohm 1 watt resistor. Use your graphing to measure the current. Checking with Ohm's law, does the graph make sense?