Intel's stock crashed nearly 30% in a single day, its worst drop since 1974, and that's bad news for the chipmaker's turnaround efforts.

• Intel shares fell from over $92 to under $66 after its earnings report, weighed down by weak forecasts, soft laptop demand, and a factory explosion in Israel that hurt chip production.
• Rising memory chip prices are also squeezing PC demand, adding another drag on Intel's business.
• A semiconductor analyst pointed out that TSMC's customers face the same weak PC demand and chip substrate shortages, yet TSMC hasn't had to cut its own forecasts — suggesting Intel's problems run deeper than the industry backdrop.
• The real issue may be Intel's own execution, weaker product lineup, and heavy reliance on fewer customers compared to TSMC's more diversified client base.

Outlook: Intel's turnaround under its CEO faces a tougher test, while TSMC looks better positioned to weather the same industry headwinds.