Test available in 8 different areas / Sylabuss

The test is available in eight different areas:
1. Biochemistry, Cell and Molecular Biology
2. Biology
3. Chemistry
4. Computer Science
5. Literature in English
6. Mathematics
7. Physics
8. Psychology

http://www.freshershome.com/careers/abroad/gre/gre-subject-test.php

Preparation Min / Max Time / Result Time

4 weeks is the minimum period and 12 weeks is maximum period. The reason, is that 4 week is not enough to get familiar with the patterns and skills required for the exam while 12 weeks is long enough that additional time will make you forget what you studied earlier since you will not have more material to learn from. Finally it depends on your readiness for the exam
ETS says that scores for the computer-based general test "will be sent to you and the score recipients you designated within 10 to 15 days after you take the test."

Format / Eligibe & Fees / Score Pattern / Regis

http://www.foreigncampus.com/test/GRE/scoringpattern.htm