Computer doesn't come on, no power?
Posted 14 November 2009 - 10:06 AM
Posted 14 November 2009 - 10:16 AM
Does the fan on the cpu stay on when the power is turned on?
Posted 14 November 2009 - 10:18 AM
Posted 14 November 2009 - 10:22 AM
If not do the following.
Disconnect everything from the Motherboard except
- video output
- 20+4 powercable
- 4/8 pin 12v wire both coming from the powersupply,
- Cpu fan wire
- power and reset button to the case
- case speaker
The goal here is just to test the mobo:
If the computer still will not boot up the please remove the motherboard from the computer along with the power supply
place the motherboard on a piece of card board larger than the motherboard,
this will eliminate a short from the mobo to the case which could be a possibility
Install the cpu with, 1 stick ram in dimm 1, power supply, case switch and case speaker
Connect ps2 mouse and keyboard along with the monitor
Repeat the above and power on
If the computer now boots into bios you most likely had a case short so make sure when installing the motherboard in the case that you use standoffs and they line up with the mounting holes in the motherboard and none of the standoffs touch anything else on the underside of the board.
Posted 14 November 2009 - 10:50 AM
To properly and conclusively test a power supply unit (PSU), it must be tested under various realistic "loads" then analyzed for excessive [url="http://en.wikipedia.org/wiki/Ripple_(electrical)""]ripple[/url] and other anomalies. This is done by a qualified technician using an oscilloscope or power analyzer - sophisticated (and expensive) electronic test equipment requiring special training to operate, and a basic knowledge of electronics theory to understand the results. Therefore, conclusively testing a power supply is done in properly equipped electronic repair facilities.
Fortunately, there are other options that are almost as good. I keep a FrozenCPU Ultimate PSU Tester in my tool bag when I am "in the field" and don't have a good spare power supply to swap in. While not a certain test, they are better than nothing. The advantage of this model is that it has an LCD readout of the voltage. With an actual voltage readout, you have a better chance of detecting a "failing" PSU, or one barely within specified ATX Form Factor Standard tolerances. Lesser models use LEDs to indicate the voltage is just within some "range". These are less informative, considerably cheaper, but still useful for detecting PSUs that have already "failed". Newegg has several testers to choose from. All these testers contain a "dummy load" to fool the PSU into thinking it is connected to a motherboard, and therefore allows the PSU to power on, if able, without being attached to a motherboard - great for testing fans, but again, it is not a true load or suitable for conclusive testing.
As mentioned, swapping in a known good supply is a tried and trued method of troubleshooting used for centuries, even by pros. Remove the "suspect" part and replace with a "known good" part and see if the problem goes away.
I do not recommend using a multimeter to test power supplies. To do it properly, that is, under a realistic load, the voltages on all the pins must be measured while the PSU is attached to the motherboard and the computer powered on. This requires poking (with some considerable force) two hard and sharp, highly conductive meter probes into the main power connector, deep in the heart of the computer. One tiny slip can destroy the motherboard, and everything plugged into it. It is not worth the risk considering most multimeters, like plug-in testers, do not measure, or reveal any unwanted and potentially disruptive AC components to the DC voltages.
And remember, anything that plugs into the wall can kill. Do not open the power supply's case unless you are a qualified electronics technician. There are NO user serviceable parts inside a power supply.
Posted 14 November 2009 - 11:03 AM
The only video output I have is for my viedo card. So, that wasn't hooked up
Posted 14 November 2009 - 11:12 AM
Posted 14 November 2009 - 11:16 AM
Can you try the other stick of memory and see if it starts with that stick. If so then seat both sticks again and try it. another option is does your MOBO have color coded memory slots?
Did you check to make sure which banks are which as some MOBO's don't actually have banks next to each other or have to have certain banks used in order for system to boot correctly.
Posted 14 November 2009 - 11:22 AM
Posted 14 November 2009 - 11:29 AM
If so then it seems you may have a bad memory module.
If this is correct then we need to get the system back together and then run memory test on the working module to make sure it has no underlining issues.
Let me know when you are ready for the next steps.
BTW good work on finding the problem.
Posted 14 November 2009 - 11:36 AM
Go ahead and direct me on how to do a memory test too. I will be back in a couple of hours. Everything seems to be fine now, with both memory sticks. But none of the usb ports work.
Posted 14 November 2009 - 11:42 AM
The first part of this please skip as we have already tested ram sticks apart from each other.
If you have more than one RAM module installed, try starting computer with one RAM stick at a time.
NOTE Keep in mind, the manual check listed above is always superior to the software check, listed below. DO NOT proceed with memtest, if you can go with option A
B. If you have only one RAM stick installed...
1. Download - Pre-Compiled Bootable ISO (.zip)
2. Unzip downloaded memtest86+-2.11.iso.zip file.
3. Inside, you'll find memtest86+-2.11.iso file.
4. Download, and install ImgBurn: http://www.imgburn.com/
5. Insert blank CD into your CD drive.
6. Open ImgBurn, and click on Write image file to disc
7. Click on Browse for a file... icon:
8. Locate memtest86+-2.11.iso file, and click Open button.
9. Click on ImgBurn green arrow to start burning bootable memtest86 CD:
10. Once the CD is created, boot from it, and memtest will automatically start to run.
The running program will look something like this depending on the size and number of ram modules installed:
It's recommended to run 5-6 passes. Each pass contains very same 8 tests.
This will show the progress of the test. It can take a while. Be patient, or leave it running overnight.
The following image is the test results area:
The most important item here is the “errors” line. If you see ANY errors, even one, most likely, you have bad RAM.
Posted 15 November 2009 - 12:03 AM
Posted 15 November 2009 - 07:17 AM
Is the system booting up with the front USb ports connected now?
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