So some results

Milkyway@Home:
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HD7950: ~37 / ~47 secs per WU; ~80 / ~107 pts per WU

Einstein@Home BRP4:
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650 Ti: ~3000 secs for 2 WUs
660 Ti: ~1200 secs for 1 WU, ~2200 secs for 2 WUs
HD7770: ~2300 secs for 1 WU, ~4000 secs for 2 WUs
HD7950: ~1050 secs for 1 WU
Each GPU WU is worth 500 pts

GPUs are clocked:
HD7950 - 1120 MHz
HD7770 - 1120 MHz
660 Ti - default
650 Ti - 1020 MHz