What can I do "spread" load on breaker for single bedroom?
If there's room in the panel, you could run additional circuits.  If not, you could install a second panel, or try and free up space in the existing panel.

If you have room for additional circuits, I'd recommend putting the A/C unit on its own circuit.  Because through normal use, the A/C unit will introduce surges and noise on the line. This is undesirable on circuits with sensitive electronics such as computers, so you should avoid having the A/C on the same circuit, if possible. 

If you're seeing dimming lights when the A/C comes on, it's likely due to voltage drop. This voltage drop is caused, because the A/C is drawing a large amount of current when the unit starts up.  This drop in voltage can be damaging to sensitive electronics.  

Depending on the load requirements of the servers, it may be desirable to install an additional separate circuit to handle them.

If possible; and depending on the load requirements, I'd recommend using three circuits. One for the A/C, one for the servers, and one general use circuit for the PC, monitors, and various other office equipment. 

Installing a larger breaker is likely not an option, unless the wiring, devices, and equipment are all rated for the higher current (not likely).