I installed an SSD (this one)
BIOS recognised it. I installed windows. Everything seemed to be fine (also the speed has increased significantly) but now sometimes the SSD is not recognised and I go straight into BIOS…
After couple of reboots it usually is ok…
Is this an issue with bios or ssd?
Angelos
Try to clean the SSD contacts with alcohol.
Did that already.
Any other ideas?
Check if SSD detects correctly and every time on other PC 
Yes I could do that…I have to find another device …
thanks
I think it is an SSD issue. You should check that it makes good contact in the slot and that it has no movement and is properly secured with the security screw.
Once these checks are done, you should perform an SSD drive error check and finally a Windows startup repair