This is the RC1 Win7 7077 build that has recently leaked onto torrent sites
Filename : 7077.0.090404-1255_x86fre_client_en-us_Retail_Ultimate-GRC1CULFRER_EN_DVD.iso
Size : 2.35GB
SHA-1: 6B4D676257C57607B951A101C7B2C559CD7A5730
MD5: BDCB388DAFFAD32D6264144C05B29700
CRC32: BFE066D4