What type of CMOS battery do I need for Optiplex GX620

If windows 7 you need to burn a repair disc & run it. Go to Maintenance, creat repair disc (use one CD & mark it with Dell gx62 on top, repair disc run first on bottom)
Restart your computer and hold down escape, F1 or F2 to get into the settings in the CMOS. You must chang the boot order of your startup. In CMOS use arrows to right to Boot to change to CD ROM then HDD so your CD will go into repair before starting the HDD. Each CMOS is different but usually you can use the f5 or f6 to change the order and f10 to exit & save the setting. Restart your computer after you put the repair disc in & that should repair your start up.

I’m happy to help further over the phone at https://www.6ya.com/expert/wynn_5ba0205233ebfc15

Please try by resitting the ram.If the problem persists try by removing the cmos battery for some time. if problem is not solved then try with another smps.if all fails then your motherboard is gone bad.

If you are getting a CMOS batter voltage low error, there is a small watch like battery on the mother board you can replace.

Hi,

• Turn the machine off and unplug from power.
  
• Locate and remove the CMOS battery.
• Disconnect the hard disk from power
• Leave it like that for a few minutes and the connect everything.
• Start the machine now.

Worked for me,hope it does for you.Thank you!

If you pull the side access cover off the computer tower, look inside and you will see a large circuit board, that is the Motherboard, on that board you will see a button sized silver battery, this is the battery backup for the "CMOS", and keeps the time and other memory functions alive. Carefully pry out the old battery and replace it with a new one, any Radio Shack or electroinics supply will have the battery. The battery number is on the battery. Make sure to install the battery exactly as it came out, it has a positive and negative side, write it down.

The solution is simple but you will need to do a little work. First disconnect the computer from its cables (I recommend getting a vacuum before you open the case.Vacuum the PC outside.) Open the case and blow out the dirt by putting the hose on the output end. If that is not a option do the best you can and **** out what you can. You might try a small paint brush to GENTLY brush off components. On the main (motherboard) board you'll find a round button battery. Pop it out and get a new one of the same type from Walmart, Walgreens or any watch store. Put it in the same way you found the old one (writing up). Close up the PC and reconnect everything. At start-up hit F-1. The PC has lost it's setup because the battery went bad. The PC will usually sense what it has, but you will need to set the time and date. Hit F10 to save and exit. After you reboot twice there should normally be no more issues. For additional instructions search changing CMOS battery on line.

plug out your power cable from the system after this plug out cmos battery only for five minute.then again plug in cmos battery and plug in power cable. your password is removed.

be sure you put back the plug properly...sometimes it needs to be pushed hard to make a good contact. If no power still, then have the power supply checked.

HELLO THERE:
THE FIRST THING YOU WILL NEED TO DO IS TO DOUBLE CHECK ALL THE CABLES AND POWER CORDS ARE FIRMLY INSTALLED NORMALLY REMOVE AND REINSTALL THE CORDS AND CABLES TO MAKE SURE THEY DID NOT COME LOOSE IF IT WONT BOOT THAN TRY TO REMOVE THE CD ROM AND THE HARDDRIVE CORDS AND CABLES FROM THE DEVICES AND TRY TO BOOT IF THE MACHINE IS NOW STARTING INSTALL THE CABLE AND CORDS 1 AT A TIME FOR EACH DEVICE AND BOOT UP THE MACHINE EACH TIME THIS WILL HELP YOU FIND OUT WHERE YOUR PROBLEM IS OK.
BEST REGARDS MIKE

type in dell gx620 audio drivers in google and you should get your drivers.

Dennis