The 780 is not overclocked. The ppd is calculated by FAHControl. The currently running 8900 is showing similar PPD. With a time per frame of 3:04, based on 10% progress below,
http://www.linuxforge.net/bonuscalc2.php shows a ppd of 156,843 (even better than FAHControl). This is all new to me, I just fired up the 780 earlier today.
Project: 8900 (Run 807, Clone 0, Gen 235) - ppd: 155144
..
23:50:16:WU01:FS01:0x17:Completed 1750000 out of 2500000 steps (70%)
23:47:18:WU01:FS01:0x17:Completed 1725000 out of 2500000 steps (69%)
23:44:09:WU01:FS01:0x17:Completed 1700000 out of 2500000 steps (68%)
23:41:11:WU01:FS01:0x17:Completed 1675000 out of 2500000 steps (67%)
23:38:01:WU01:FS01:0x17:Completed 1650000 out of 2500000 steps (66%)
23:35:04:WU01:FS01:0x17:Completed 1625000 out of 2500000 steps (65%)
23:31:54:WU01:FS01:0x17:Completed 1600000 out of 2500000 steps (64%)
23:28:56:WU01:FS01:0x17:Completed 1575000 out of 2500000 steps (63%)
23:25:46:WU01:FS01:0x17:Completed 1550000 out of 2500000 steps (62%)
23:22:48:WU01:FS01:0x17:Completed 1525000 out of 2500000 steps (61%)
23:19:38:WU01:FS01:0x17:Completed 1500000 out of 2500000 steps (60%)