You haven't described your hardware -- but
here is a benchmark of Drupal 7 service all contained on the same computer. They were able to achieve just over
eight and one half transactions per second. (0.03 transactions per seconds, with 286.21 average users).
This is 1-2% of your desired transaction rate.
The hardware and software used for that benchmark: a dual core AMD 64 X2 2.2GHz, 2GB RAM, 160GB SATA disk, with Ubuntu 8.04.1, Apache 2, MySQL 5.0, PHP 5.2.4.