![]() ![]() 3 x AAA battery holders can be picked cheap on eBay HERE. Think of old batteries in remote controls and what happens to those. These will probably last 3-4 years before corrosion sets in, so mount these battery packs using velco tabs well away from the mainboard. Beware of long term corrosion of alkaline batteries. Incidentally, some original mainboards came with 4.5v external lithium batteries installed. The 3 x AAA batteries give a total voltage of 4.5v which is above the original 3.6v, however it still works fine and I’ve never lost a mainboard using this method. Plug leads can can be hacked from PC speakers and also some CDROM audio leads also work. Attach this to the external battery connector on the motherboard, but you’ll need solder on a 4 pin plug and lead. DIY external battery holder using 3 x AAA alkaline batteries: Make your own external battery using AAA batteries.These can be purchased quite easily on eBay HERE. External 3.6v lithium battery pack with leads: Many 286, 386, 486 motherboards have provision to take an external battery.Severe corrosion often destroys the copper PCB tracks resulting in a non working board.Ĭleaning: What you need to clean up the the mainboard. Inspection: Check the condition of the copper tracks around the battery and nearby components. If you have compressed air available, blast off excess water with an air gun. After doing this rinse the area with distilled water and soak up any remaining water with tissue paper and then let dry. White vinegar also seems to work quite well as it neutralizes the alkaline battery leakage. If the corrosion is more severe, then use a bicarbonate soda / distilled water solution to scrub down the affected area, again using a toothbrush. This will remove any of the soldering flux and residue.Īny light corrosion around the battery area can be cleaned off with methylated spirits also. Mainboard cleanup:Ĭlean the board with methylated spirits or isopropyl alcohol using a toothbrush. Clean up excess solder with de-soldering wick.īattery removed…and to now clean up the board. Take caution not to lift the solder pads or copper tracks when de-soldering the battery. If the battery has hot melt glue holding it to the board, then break the glue bond by rocking the battery back and forwards a few times. ![]() Some batteries are not always that easy to cut off, so they must be de-soldered.ĭe-soldering the CMOS battery: Use a soldering iron to release one leg at a time. Probably the easiest method and least likely to cause damage to the motherboard. The longer they are attached to the board, the more chance of them leaking and starting an ingress of corrosion…which you don’t want. Old NiCd and NiMH batteries should be removed from motherboards as soon as possible. Old NiMH CMOS batteries are also susceptible to leakage and corroding the motherboard. NiMH (Nickel Metal Hydride) rechargeable: Similar to NiCd but without the environmentally unfriendly cadmium. SMD resistors and copper tracks are being eaten alive. Check the hot melt glue between the battery and motherboard. Notice how the corrosion is spreading to nearby components and ruining this 386 motherboard. NiCd CMOS battery: Typical 3.6v NiCd CMOS battery by Varta. Many PC motherboards used batteries made by Varta. Old NiCd and NiMH batteries are notorious for leaking corrosive substance over the motherboard which can ruin it forever. They have a life span of 5 to 10 years depending on the amount of use, environmental conditions such as heat and humidity and the quality of battery. They are rechargeable 3.6 volt type batteries which are recharged each time the PC is powered on. These batteries are mostly seen on 286, 386 and 486 motherboards from the 1980’s through to the mid 1990’s. External wired lithium non rechargeable 3.6 volt.Rechargeable NiCd & NiMH soldered to motherboard 3.6 volt.PC’s have used a variety of different battery types since their inception in the 1980’s. The CMOS battery is responsible for supplying backup power to the CMOS Real Time Clock (RTC) which stores date, time and hardware settings such floppy drive type, hard drive parameters, memory, cache settings and various other chip-set settings for the BIOS. Here is a guide to replacing CMOS batteries in old PC’s. An annoying inconvenience each time you start your PC. Without a working CMOS battery all the BIOS settings including time, date and hard drive parameters will be lost when you turn off the PC. All looks fine, until you hear beep beep and get this warning :Īt least the PC still works, but the last message is a sure sign the CMOS battery has died and needs replacing. You’ve just fired up your old PC, the screen comes to life with the usual BIOS messages and memory count.
0 Comments
Leave a Reply. |
Details
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |