All of IBM's major competition has come out and used Europe as headwinds. All of them (ACN, ORCL, and INFY) has seen 8-10% declines when reporting the news. Since IBM hit its all time high (195), the stock is off about 8%. When Oracle reported their short-fall IBM was near 187. Using 187 as a base, an 8-10% decline 187 is 172-168, respectively.
Technically, there is support below 187, and strong support near the low 170s via the 200SMA.
Assuming IBM sees the low 170s suggests the market starts discounting sector negativity from 187. If we assume macro negativity was being discounted from 195, anyone of the above supports can be used as an entry. (I am conservative, so I used the 187 number.)