The customer feedback shows that after IdeaPad Z370/Z470 machines wake-up from sleep in Windows 7, the read speed or data transfer rate of hard disk dropped significantly. By running Hard disk performance software, such as HDTUNE comparison test, we found that read rate of hard disk decreased significantly.

As shown in the following figures, HD TUNE V4.6 comparison test results are as follows:

In Windows 7 (before sleep), the average data transfer rate: ~75MB/s

Fig.1

In Windows 7 (wake-up from sleep), the average data transfer rate: 13MB/s. According to testing results, the data read rate of hard drive dropped significantly.

Fig.2

The above symptom may occur to the following systems:
IdeaPad Z370/Z470

To the following operating systems:
Microsoft Windows 7

This is a bug inside Phonenix BIOS and it can be solved by updating BIOS to version 4ACN38WW.

Please click the following link to download BIOS Update for Windows 7 (32-bit, 64-bit) - IdeaPad Z370/Z470

http://support.lenovo.com/en_US/downloads/detail.page?DocID=DS032844