I have a thinkpad T440p, i have replaced the CMOS because it died on me, but now after a while of getting the new one my PC is behaving weirdly, it takes three tries to turn it on. First time i turn it on and it tries to start but shuts off; the second it tries but shuts off much quicker with a strange sound that seems like the speaker suddenly disconnecting and then it works flawlessly on the third try. Is the CMOS the problem here?

Yep, the issue is probably the battery, since it’s so old and in horrible conditions