Previously Intel had also talked to Bain and San Francisco Partners about an Altera deal but now the discussions are said to be solely with Silverlake.
Intel bought Altera for $16.7 billion in 2015. Analysts have valued the unit at around $9 billion.
Intel announced that it would be selling Altera last October.
Last June, Intel sold a 49% stake in its Fab34 in Leixlip near Dublin for $11 billion to the private equity company Apollo Global Management.
Reports persist that Broadcom could buy Intel’s product divisions and TSMC could manage Intel’s advanced fabs under some sort of joint equity arrangement,