Investors missing out on these hot stocks: Jim Cramer

Investors missing out on this hot sector: Cramer

One of the hottest industries today also happens to be under invested, CNBC's Jim Cramer said Monday.

So what's the industry? Data storage devices: those technology companies that make hard disk drives, servers, mainframes and other things that go inside personal computers.

"This group is where the action is and I gotta tell ya, people are still under invested in what I regard as being 'old tech,'" said Cramer on "Squawk on the Street."

Jim Cramer
Adam Jeffery | CNBC

Given the advent of cloud computing, in which data is managed and stored on a network of remote servers instead of on a personal computer, the data storage devices industry might seem a little old fashioned.

Read MoreWhat's cloud computing? CNBC Explains

But for whatever reason, "old tech" has picked up steam lately.

Wall Street analysts recently raised their price targets on Seagate Technology and Western Digital, for example. Seagate will deliver its quarterly earnings report on Thursday.

Read MoreCramer'splan: 10 earnings plays for this week

Intel, which will post earnings on Tuesday, had earlier pre-announced to the upside. Historically, "big blue" has not pre-announced earnings unless the company could beat the pre-announcement, Cramer said.

"I look for Intel to go higher. Old tech is doing so well," he said. "If it's in a PC, it's going higher."

—By CNBC's Drew Sandholm.

DISCLOSURE: When this story was published, Cramer's charitable trust did not own Intel, Seagate Technology, or Western Digital.