Laptop: Dell Studio 15, Intel® Core™ i7-720QM mobile processor (1.6GHz, turbo up to 2.8GHz, 6MB L3 Cache)
OS: Windows® 7 Home Premium, 64bit
Graphics Card: ATI Mobility Radeon™ HD5470 1 GB
Hard drive: Serial ATA 500 GB

In 2015, I gave my laptop to the computer service for inspection and cleaning. Nothing special. Standard procedure advisable from time to time.

After receiving it from the computer service, during use, the laptop quickly warmed up like never before. After two weeks, the motherboard of the laptop burnt.  I am an average computer user and I had no idea what could have happened. Interestingly, the computer service was closed down. In the meantime, I only pulled out the hard drive from the laptop, which turned out to be undamaged and all files were saved.

Currently, I am assuming that during the service, a malicious software could be installed on the laptop to mine cryptocurrency, maybe bitcoins, maybe another crypto. I do not know, I just suspect. Fortunately, I still have this hard drive and I would like to check somehow if this suspicion might be right. And if so, are some cryptocurrencies kept on the hard drive?

I will be grateful if anyone can give me a clue how to check it out.

Thank you in advance for any help.