20 Most Recent Dell OPTIPLEX 960 MT Desktop Computer (Intel Core 2 Duo E8400 250GB2GB) (BO5SC306) Questions & Answers

bad capacitors were the bad boys , i have replaced the starting capacitor valued 1000uF 10v just across the switching IC and it worked

Dell OPTIPLEX... | Answered on Dec 20, 2016

Hi Carlos, error code 3 & 4 is caused by faulty RAM (Memory modules) installed in the PC. You could try the following to resolve the issue:

1. Open up the computer cover
2. Locate the memory module(s)
3. Remove them memory module(s)
4. Use a can of compressed air or spray contact cleaner onto the center of the DIMM connectors to clean all the contacts. Do NOT use a normal brush to clear dust away. Wait for 5minutes for the contact cleaner to dry.
5. Reseat the memory module(s)
6. Turn on the computer and check if codes 3 & 4 still light up. If it does not, it should boot into the Operating System.
7. If codes 3 & 4 continues to light up, you will need to run a memory diagnostic test to determine which of the memory module is faulty.

Dell OPTIPLEX... | Answered on Sep 07, 2016

OS is corrupt and needs to either be repaired or reinstalled.

Dell OPTIPLEX... | Answered on Oct 22, 2015

Hi Tiffany,

it sounds like there has been some sort of corruption of the files on the hard disk. You should see about booting from the Windows installation CD / DVD and copying all the files that are of importance to you (documents, photos, music, etc.) on to an external hard drive connected to the USB port or installed as a slave drive internally. Once you have saved all the files you need, shut off the PC and disconnect / remove the drive with your files. Then reinstall Windows again. Once done, shut off the PC and reconnect the drive with your files and copy them back to the hard drive and you should be good to go unless he drive is beginning to fail - in which case purchasing a new hard drive would be a good idea.

Dell OPTIPLEX... | Answered on Aug 10, 2015

According to Dell you will need to run their diagnostic utility to find out what is really causing this error code


read the part about how to start dell diagnostic

Dell OPTIPLEX... | Answered on Feb 27, 2015

Best way is to contact your service provider. I have Verizon and they're a big help for that.
Hope this helps.

Dell OPTIPLEX... | Answered on Feb 21, 2015

Hey, have you ever thought that you ANSWERED YOUR OWN question? If you press the power supply TEST button, then it powers up fully? It's NOT the button.......So...what else could it BE then Mitch?

Dell OPTIPLEX... | Answered on May 01, 2014

Could be several things.

1. could be the power supply
2. inspect the motherboard for bad caps.

If the above is OK. Try removing and reseating the CPU, Memory and CMOS battery.

Dell OPTIPLEX... | Answered on Apr 16, 2014

Probably needs a new power supply or power switch.

Dell OPTIPLEX... | Answered on Sep 22, 2013

Sounds like your on Google Chrome, this has started popping up since the last update and only on secure webpages at random, try running Windows Update and make sure it's up to date, it check the root certificates which should come with the windows updates.

Dell OptiPlex... | Answered on Oct 22, 2019

ok 960 SFF is not the same as MT or the big case MOBO.
SFF has its own mobo (motherboards)
it has 11x2 row non ATX spec, power . not yours as it has 12x2 some SFF have 2 diffr. mobo
and a dell custom PSU for just this mobo and its odd duck jack. (called PICO plug)
why not buy a new PSU? that matches this PC?
even the SFF PSU case is not ATX spec.


Dell OptiPlex... | Answered on Feb 23, 2019

Go into device manager. Uninstall audio driver.

Restart computer.

This will reinstall the default driver. Try again.

If it doesn't work, go to Dell website to find specific driver for your computer (using the service tag) and install that.

Dell OptiPlex... | Answered on Oct 08, 2016

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