Is my SSD dead even though it shows 99% health?

Honestly, I think it's dead too. A 99% health marking doesn’t guarantee it can't fail. SSD health metrics mainly reflect wear from writing data, which means other failure types—like controller issues—won’t show up there. If you're hoping to recover data, best of luck! You might need professional help, though.

The health metric you’re seeing only measures wear on the flash cells from writes. Other hardware issues can’t be predicted with that metric. It’s pretty common for SSDs to die abruptly despite showing good health initially.

I've not heard of that brand either, and it's pretty sketchy. It sounds like it doesn’t have DRAM, which means it’s gonna slow down as the cache gets filled. Plus, who knows what kind of controller or memory it has! All these factors can lead to early failure. If it overheated for any reason, that could have contributed too.

Sounds like your SSD might be on its last legs. With XrayDisk products, it's not uncommon for issues to arise. Their warranty period is usually pretty short, around 3 to 12 months, so your situation isn't surprising. You could try connecting it to another PC to see if it works there, but chances are slim. It's probably a sign to get a new SSD from a more reliable brand. Sorry to say, but it might be time to replace it!

Haha, 'Brand X' is the perfect name for this product! It's a bit of a joke in the tech world. But seriously, it does look like a classic case of a budget SSD failing on you. I hope you have backups of important files!