Can't boot, Gigabyte GA-P35-DS3L echoing 3 long beeps, pauses and then continuously long beeps

[w7089]

Computer stopped working after working flawlessly for over 10 years.
Immediately after switching on the computer, beeping starts.
After 3 long beeps, beeping pauses, CPU fan starts, long beeping continues endlessly.
The beeping pattern is not documented in motherboard manual.
The closest beeping patterns i found were:

Continuous long beeps: Graphics card not inserted properly
Continuous short beeps: Power error

All the fans (CPU, rear, power, graphics card) are working.

What may be the reason - broken CPU, graphics card, power ?

 

[rocktalkrock]

Here is a list of different beep codes. - https://www.computerhope.com/beep.htm

If you have more than 1 stick of RAM, try booting with a single stick, then switch sticks and try again.

 

[w7089]

The issue was with one of the memory sticks. Got it out and the computer runs.