Hi, my 518 won't power up, front LEDs,HDD, Fan come on for like 2 or 3 sec, then computer goes off after a short beep, after 4 or 5 sec everything starts again on and on and on. Tried new PSU same thing, what else can I try?, Is it a hardware or a software problem?...
This is a hardware issue.
Remove all the RAm from the system then try powering the system back up placing one stick of RAM in the system at a time, cycling through each individual stick of RAM. If it powers on with each stick individually then add a second stick, cycling the second with the remaining RAM modules. Do this until you can isolate a single stick as point of failure (if possible).
Sometimes reseating all the RAM fixes odd ball issues like this. If it does not resolve this issue let us know & we'll go from there.
Also: when you are replacing the RAM make sure you unplug the system from all power sources.
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Assuming the new power supply is good, it would point to a motherboard problem. Unfortunately there is no way to test the motherboard other than to replace it. Same way if the CPU was suspect.
One thing to try. Disconnect the 24 pin power connector from the motherboard then (with the AC power cord connected) jumper the GREEN wire to a BLACK wire in the 24 pin connector and see if the power supply comes on and stays on. If it does stay on it doesn't say the power supply is 100% good but it does point back to a probable motherboard problem.
Another is disconnect everything from the motherboard - the hard drive, any optical (CD/DVD) drives and if you have any expansion cards installed such as a Video Card, sound card, etc remove them. Then try powering on and see if it changes. If you still get the same indication it's back to a probable motherboard problem. However, if symptoms change is suggests one of the devices you disconnected is causing the problem. Start by connecting one at a time until you find the problem device.
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Well I removed all memory from the board and the computer didn't turn on but it did beep different like when you are having a memory issue(LEDs light blue +3 quick beeps and then turn off), by the way I had to reset the memory about 3 times in the past, this time the computer was hibernating and never came back to live when I hit the power button. Could it be the memory?, what's the symptom if I try to turn my PC on without memory?
the first thing that I tried was a new PSU, to my surprise it didn't fix it, so I disconnect everything from the MoBo, same problem, disconnect Microprocessor and clean heatsink fins and fan, nothing, am getting kind of frustrating here...I'll try the memory today(probably gonna buy 2 sticks)...
If trying it with just the RAM (and CPU of course, you have to have that in there) doesn't work then I'd say bad motherboard.
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