It was estimated the ELO of some of the strongest programs, mixing results
against humans with computer-computer results, and extensive
experiments(elhchess.demon.co.uk).
Here is the list:
Deep Fritz 8 on Quad/1000: ..........,2798
Deep Blue Jr 9. on Quad/1000: ........2772
Deep Blue Jr.9 on Dual/1000:..........2742
Shreder 8 on standard powerful:.......2732
Deep Fritz 8 on Dual/1000: ...........2728
Shredder9 on standard:................2718
Hiarcs9.6 MAC.........................2714
Fritz 8, running in standard last generation CPU achieves an ELO close to
2700. Other programs were not considered in the analysis, but some of them
are missing, like the last versions of Chessmaster, Rebel, and X3D Fritz.