Question Lenovo Thinkcentre M93: two beeps after changing from Legacy to UEFI, no display and no POST ?

[MasterCookieUY]

Some days ago a friend of mine gave me his Lenovo Thinkcentre M93 to fix something related to drivers, screen resolution and told me someone changed something in the BIOS. PC would boot until I entered the BIOS and without thinking I changed boot options from Legacy to UEFI. After saving and exiting the PC wouldn't boot and after some seconds it made two short beeps. I tried:

• Removing the CMOS battery for five minutes (also tried putting it upside down),
• Clearing the CMOS putting a jumper in the right place,
• Removing all ram sticks (which caused the PC to beep differently),
• Removing some ram sticks and leaving some, changing their positions,
• Disconnecting the HDDs
• Tried to remove the GPU but I applied too much force and broke the clip

I don't know what else to do. I read that two beeps means ram or board failure, but since it's a Lenovo PC I don't think that any other motherboard would fit in the case and neither my friend or I have any money to buy new components. Mistakes I made were:

• Removing the CMOS battery and other components without an antistatic wristband so I think I could have have fried something with ESD.
• Not disconnecting the AC power cable from the PSU which doesn't have a switch, so the PC turned on instantly when connecting it to the power outlet.

People on Reddit told me to get and try other RAMs with I got today. What can I do? Sry if bad English.

 

[T_T]

Try replacing the CMOS battery.

 

[ex_bubblehead]

Try replacing the CMOS battery.

This has nothing to do with the CMOS battery.

The problem is that the OP changed the boot option from Legacy to UEFI. This cannot be done without a full wipe and reinstall. Everything after that simply exacerbated the problems.

But, seeing as he hasn't been back since 26 March we may never know.