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

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.

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

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.

According to Dell you will need to run their diagnostic utility to find out what is really causing this error code http://mss.net/Links/DellDocs/OptiGX260/UserGuide/advtshoo.htm#1163831 read the part about how to start dell diagnostic

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

It sounds as if your power connector is not seated correctly See error light codes in this manual http://support.dell.com/support/edocs/systems/op960/en/setup/setup_en.pdf

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?

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.

Probably needs a new power supply or power switch.

Larry provides great information. Larry Ng Apr 30, 2022 good news the not told at all PC screen is not dead. a major fact but lacks all evidence like: 1, No PC told no OS told xp to w11 2: fans spin? all do, psu ,cpu and gpu card if fan. 3: Optiplex is a desktop 29 years of models made wow. 4: you mean Dell Splash logo. yes, and then it does the post bar, if post bar stalls that means hardware gross errors. sadly no PC model told of vast versions. wow. just wow hopeless that.? but is par here, and vast wrong answers just for that fact alone.even mine. i have many optiplex PC here old and new and my fav is 9020MT or smaller my oldest is 380(in storage) is your coin cell dead. (if yes can NOT be ignored) my dells all have F12 diagnostics, power on and hammer F12,, pick diag eSPA and run it older PCs dell if the HDD is dead the F12 diag is dead. due to being located there back long ago. my dells have a BIOS log page, go to BIOS the click tab, LOG read the logs. see what fails. (coin cell RTC sure)_ easy no?\ but why on earth post lacking the model number making any useful simple help 10 pages long for 29years of models. 1993 is the first OptiPlex, seen here. https://en.wikipedia.org/wiki/Dell_OptiP... nobody can guess and no era is the same. evolution max. ..

What is the exact error that you are getting? Do you get any blue screens? Have you installed any software recently or made any changes? I can only suggest checking the power cables and trying to use a different cable or spare if you have any for now.

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.