INSPIRON E1705 external GPU

hello a greeting to the community, I have a Dell inspiron external gpu for dell inspiron e1705 with these characteristics ,genuine intel CPU T2300 1.66GHz*2 memory RAM 3.2 gib hard disk 120 GB the video card AMD ATI RV15/M54 mobility Radeon *1400 VGA controller. which external GPU could I use?