I have a problem printing from PC because printer breaks when print circle and that makes blobbing.
But that happends only when printing from PC, when printing from SD card directly it is ok.
What can be wrong???

If the circle has to many segments the printer can empty its buffer and momentarily stop while it waits for more data from the pc. This is slower than loading from SD

check you baud rate is 250000

make sure to use an few segments as possible while still giving you good results