I had a HP computer (Intel Quad Core Q6600) go up on me. One morning, the system wouldn't turn on. Pressing the case switch did nothing - as if it wasn't even plugged in at all. Through some online research and testing, I decided the problem was the motherboard. So, I purchased a new motherboard, swapped everything over, and it wouldn't still wouldn't turn on. So, I purchased a new PSU, since that seemed like it was the next solution. That arrived today, and I installed the new PSU.
I powered the computer on, and entered BIOS. Everything seemed OK there, so I switched it to boot from CD to load the OS. While loading the OS, the computer died. Just like that, BAM! No power. At first I thought we lost power to the house, but quickly realized everything else was still on.
One thing of note - while it may seem inconsequential - when I brought the tower back into the office, I used the cord from the old PSU that was already routed through the desk. After it died and before further troubleshooting, I switched the power cord to the one that came with the PSU and used a new wall outlet.
I've shut off the system, and turned off the PSU with the switch on the back, then after the motherboard light turned off, I'd wait a few seconds then turn the PSU switch back on. Then motherboard light would come on, and when I pressed the case switch to turn on the system, both the CPU fan and Case fan would spin very gently then coast to a stop. This happened about 4 or 5 times. Now even they won't turn.
Everything seems to be hooked up properly, and like I said above, I was actually into the BIOS and was just starting to load the OS when it died.
I'm so frustrated now....I feel like I've wasted a lot of time and money.....
Its possible the first PSU has damaged some components. That could be anything from the mobo to video card to hard drives...
You say you bought a new motherboard. Its possible that the mobo you recently purchased may not be updated to work with your CPU. The symptoms you speak of could indicate a BIOS update is needed.
I think it may be helpful for us to have a detailed list of your components, in order to diagnose the problem accurately and save you time and money.
A good idea when you are unsure of where the fault may lie is to strip the system down as much as possible. Try booting with just the mobo, 1 stick of ram, & the CPU. Check to see if you can get into BIOS. If you have onboard video, try to boot without the video card (if you have one).
Throw the old power cord away so it is not inadvertently used again.
Core 2 Quad Q6600 (K) 2.4 GHz
1066 MHz front side bus
Intel G33 Express
Motherboard Name: IPIBL-LA
HP/Compaq motherboard name: Berkeley-GL8E
Memory Installed 3 GB
Speed supported PC2-5300 MB/sec
Type 240 pin, DDR2 SDRAM
400 GB SATA 3G (3.0 Gb/sec)
16X DVD(+/-)R/RW 12X RAM (+/-)R DL LightScribe SATA drive
I bought an ASUS P5G41C-M LX motherboard and new HDD (1TB) and swapped over the CPU, RAM, DVD-RW drive and PSU. When I got it all together, I plugged it in and absolutely nothing happened, just like before. So, believing it was then the PSU, I bought a Corsair 400W PSU. I swapped the Corsair PSU in, hooked it all back up and it booted into the BIOS. I was too slow to hit the DEL to actually get into BIOS, so I was stuck in a loop asking for something I can't recall now. So I powered it down, rebooted and hit DEL into BIOS. I set it to boot from the DVD-RW drive, inserted my Ubuntu disc, and Save/Exit BIOS. Ubuntu started fine, and I started the process to load the OS. I got a few questions in when it suddenly shut off.
Now, after posting the OP wondering about a bad CPU, I took the Corsair PSU out, and swapped it into this computer (the one I'm online with right now). It spun the CPU and Case fans for a millisecond, then nothing.
The two computers are set up on different outlets and different surge protectors. The original surge protector is aging, and I'm now wondering if that is the problem - that it zapped the old PSU, and then when I plugged the new one in to the old cord that was still in the old surge protector, it zapped that one.
Also, to note, the original HP PSU has a LED light on the back of it. It would come on when the 24-pin connector was disconnected form the motherboard, and both motherboards connected to the Corsair PSU had their lights come on, but still not do anything.
Sorry, I know I'm a bit all over the place - I hope you all can make heads or tails of it....