When you replaced the CMOS battery (CR2032) then the system reverted to the default boot configuration settings.
Very likely then that one or more of those settings is the culprit.
For example: the system may have been configured for some "fast boot" but is now going through some full (and longer) boot process.
All the more so perhaps with a mix of varying components etc. to "sort out" during boot up.
This motherboard?
https://www.manualslib.com/manual/451736/Ecs-G45t-M2.html
(Do verify that I found the applicable manual.)
Double check all connections and configuration settings.
Chapter 3.0 covers BIOS.
Take a close look at each availble configuration setting.
First, to understand what the setting does.
Second, to make note of the current (likely default value) setting.
Third, to test another setting value/option.
Remember to change only one thing at a time ande keep notes.
Recommended: Explore BIOS first without changing anything. Just, again, make notes regarding anything that seems amiss or otherwise not as expected. Use cancel or ESC as necessary to avoid accidental changes.
For example, from the User Manual:
"Quick Power on Self Test (Enabled)
Enable this item to shorten the power on testing (POST) and have your system start
up faster. You might like to enable this item after you are confident that your system
hardware is operating smoothly"
May not be the issue per se; but something, among many things, to check....