I have a custom-built, 10 year old desktop computer using the ASUS AMD-chip M4A88TD-M motherboard. Here are all the pertinent specs (I hope) for my system obtained by the "Speccy" app.\n\nOperating System\n Windows 7 Professional 64-bit SP1\n CPU\n AMD Phenom II X6 1090T\n Thuban 45nm Technology\n RAM\n 16.0GB Dual-Channel DDR3 @ 803MHz (9-11-11-29)\n Motherboard\n ASUSTeK Computer INC. M4A88TD-M (AM3)\n Graphics\n FHD2401 (1920x1200@60Hz)\n 3067MB ATI Radeon HD 4250 (ASUStek Computer Inc)\n Storage\n 931GB Samsung SSD 860 QVO 1TB ATA Device (SATA (SSD)) (C: Windows Partition)\n 931GB Seagate ST31000528AS ATA Device (SATA ) (E:)\n 3725GB Western Digital WD easystore 25FA USB Device (USB ) (F:)\n The C: drive is all Windows Partition, the E: drive has all the User Profiles, the F: drive is for backup\/restore and system restore points\n Optical Drives\n ATAPI iHAP222 9 ATA Device\n Audio\n AMD High Definition Audio Device\nOperating System\n Windows 7 Professional 64-bit SP1\n Computer type: Desktop\n Installation Date: 7\/5\/2010 9:45:39 AM\n Serial Number: JY467-933T7-YWJWM-4CP8W-H6QJB\n Windows Security Center\n User Account Control (UAC) Disabled\n Firewall Enabled\n Windows Update\n AutoUpdate Not configured\n Windows Defender\n Windows Defender Enabled\n Antivirus\n Antivirus Enabled\n Company Name Webroot\n Display Name Webroot SecureAnywhere\n Product Version 22.214.171.124\n Virus Signature Database Up to date\n Antivirus Enabled\n Company Name Webroot\n Display Name Webroot SecureAnywhere\n Product Version 126.96.36.199\n Virus Signature Database Up to date\n .NET Frameworks installed\n v4.7 Full\n v4.7 Client\n v3.5 SP1\n v3.0 SP2\n v2.0 SP2\n Firefox (default browser) V67.0 (64-bit)\nInternet Explorer\n Version 11.0.9600.19374\n PowerShell\n Version 2.0\n\n About three weeks ago the Windows 7 Op\/Sys clock stopped running overnight with the power off the computer. Then about a week ago, it resumed maintaining accuracy overnight with the power off. Go figure.\n\nI attributed this probably to the CR-2032 Lithium 3V motherboard battery being on the verge of failire, because the battery has not been change since I purchased the computer. I downloaded the ASUS document describing how to change the battery, but I am hesitant to change it without knowing the effect on the BIOS settings without any power on the motherboard. The document does not mention any risk to the BIOS settings, but what is the purpose of the battery except to maintain the BIOS when the AC power is off? I need to know the risk of losing my extensive BIOS settings by changing the battery before proceeding.