When the motherboard is plugged into the mains but not up and fully running, this prevents the battery having to power the CMOS chip to keep all your BIOS settings and time/date etc remembered. If you're the sort who unplugs their PC from the mains every night, this will mean the battery has to work harder but going flat so soon does surprise me
What peripherals do you have plugged into the computer eg any USB devices and what happens if you also unplug these and the ethernet cable when you unplug the PC from the mains (and then of course plug them back in again just before powering things up the next time). Maybe the battery charge is leaking away due to something plugged into the system (even though that shouldn't happen)?
Have you installed all the latest Intel drivers for your board, starting with the Chipset drivers and then including the Management Engine, Graphics, LAN and Audio drivers or are you just using native Windows ones? Are the BIOS settings at default values (obtained by loading default values and saving out of there)? Even after flashing a new BIOS version as you have, it's a good idea to load and save default values.
Honesly, I don't prefer to unplug power cord from main supply every night, until unless extremly required. However, I do shut the system and then switch off the main power supply button. I hope this doesn't make any difference, as no one wants to keep their main power supply button always - ON.
As I updated earlier, I had changed the battery twiced and last one around one month back. So trust, the battery must not have drained / empty.
I have pluged-in basic component such as internal SATA Hard-drive, SATA DVD-Writer, USB Keyboard, USB Mouse, External Speakers (having external power supply & I always make it on only after system comes online) and Ethernet Cable.As suggested by Mr. Andre B, I have updated my system with most recent BIOS and system drivers (as described below). Also, Windows 7 is updated with most recent patches (as per windows update site).BIOS Update - v0060 (SWQ6710H.86A.0060.2011.1220.1805)
Audio: Realtek* ALC Audio Driver - v6526
LAN: Intel® PRO Network Connections LAN Driver - 16.8
Graphics: Intel® HD Graphics Driver - v184.108.40.2069
USB 3.0: Renesas Electronics* USB 3.0 Driver - v220.127.116.11
Intel® Desktop Utilities - v3.2.1.042a
RAID: Intel® Rapid Storage Technology Driver - v10.6.0.1022
Intel® ME: Management Engine Driver - v18.104.22.1689 MEI-SOL
Intel® SATA Status Utility - v22.214.171.124
Chipset: Intel® Chipset Device Software - v126.96.36.1990As per BIOS update guidelines, after updating it I do have loaded BIOS default settings and tested the system. However, no positive results.Based on above information, please do let me know next plan of action / steps to resolve it.Thanks in advance.----santoshs.
Since you've already created a ticket and are dealing with Andre B, it's best that you continue to deal with him to get this resolved. This is a community forum and we are volunteers so I don't want to make things too easy for Intel Tech Support
What do you mean by you now have no positive results - what were you expecting? Your reported problem was the CMOS Checksum error and the BIOS loosing it's date and time setting ie appearing as if the battery keeps going flat. Even after doing all you have and replacing the battery with a brand new one, is it still behaving this way (straight away after changing the battery)? If so, you should get back to Intel tech support to see what they suggest in case you have a faulty board (and just leave it switched on at the back of the PSU in the meantime - although this is less than ideal for the environment and wastefull, over a month or so, it shouldn't affect your power bill much as the standby consimption will be minimal (at least compared to when the PC is fully up and running).