Tektronix 4051 © 1974 Tektronix.
This used a Motorola MC6800 microprocessor with a maximum of 32 KB of RAM. The 1024 by 780 display was a storage tube that would hold the image itself.
The Tektronix 4051 Graphic Computing System was introduced in October 1975 for the base price of $5,995.