Hi,
We have not release much information regarding x90 appliance yet, however below is the datasheet that available at the moment
http://www.cisco.com/c/en/us/products/collateral/security/content-security-management-appliance/data_sheet_c78-729630.html?cachemode=refresh
Once further information is available for Sx90 hardware, most likely will be available in below link:
http://www.cisco.com/c/en/us/products/security/web-security-appliance/index.html
