This is just taken from nCipher postings, but I like to have it around for personal reference:
The table below correlates each nShield Model with its corresponding Speed Index. Model Speed Index Edge 12 500 544 1500 1506 6000 5792 500+ 552 1500+ 1504 6000+ 4512 XC Base 478 XC SCAP 5343 XC Mid 7922 XC High 15843 There is also a Speed Index in the Server Section of the command, enquiry. This is the sum of the speed index of all the modules the server can access. Model numbers Model numbering conventions are used to distinguish different nShield hardware security devices. In the table below, n represents any single digit integer. Model number Used for NH2047 nShield Connect 6000 NH2040 nShield Connect 1500 NH2033 nShield Connect 500 NH2068 nShield Connect 6000+ NH2061 nShield Connect 1500+ NH2054 nShield Connect 500+ NH2075-B nShield Connect XC Base NH2075-M nShield Connect XC Medium NH2075-H nShield Connect XC High NH2082 nShield Connect XC SCAP NH2089-B nShield Connect XC Base - Serial Console NH2089-M nShield Connect XC Mid - Serial Console NH2089-H nShield Connect XC High - Serial Console NH3003-B nShield Connect CLX Base - Serial Console NH3003-M nShield Connect CLX Mid - Serial Console NH3003-H nShield Connect CLX High - Serial Console nC2021E-000, NCE2023E-000 nToken PCIe nC3nnnE-nnn, nC4nnnE-nnn nShield Solo PCIe nC30n5E-nnn, nC40n5E-nnn nShield Solo XC PCIe nC30nnU-10, nC40nnU-10 nShield Edge
Anyone know how the PCI cards compare, and/or why the 6000 seems to be faster than the newer 6000+?