SSD Kingston SV200S3/64G definition in BIOS?

Question

Solid State Drives

The essence of the problem is as follows:
When buying a disk, it had a firmware version: E111008a. The manufacturer's technical support offered to update the version for more stable operation.

Release Notes for SV200S3, Firmware Rev. E120506a (05/18/12)
• Improved write performance
• Optimized 4KB random throughput
• Enhanced start-up time

After the update, the disk is no longer detected by the system for booting (Boot Menu, Boot Order). If the device is secondary, then when the OS is loaded from the HDD, the disk is in the system and works fine. The same thing happens if I put the SSD in my pocket.
In order not to blame the controller, I connected it on different systems in different SATA modes (IDE.AHCI). Doesn't solve the problem.

Answer 1

And on it the MBR-record was definitely not damaged?

Answer 2

is it possible to downgrade the firmware? In general, I would contact the manufacturer.