I bought a new graphic-card and put a spare hard-drive in my old pc (got myself a new one). Then I installed freshly Windows 7 professional again and the PC worked fine for a few months.
I don't know if this is relevant, but if the PC wasn't used for a while it went into sleep mode, sometimes left alone for a few days, but mostly used a few times a day.
Then sometimes the PC gave a blue screen, when it did, I just rebooted the PC to find it running fine again for some days.
This went on for quite some time until one day it became so bad that I decided to try to repair the thing later on and put it away for now.
The symptoms the PC was showing near the end was the following:
- Regular blue screens, sometimes minutes in between.
- Hangs right after logging in.
- In the end the PC would just go on, and do nothing pretending it was very busy with something.
This is what I tried to find/solve the problem:
- I checked the hard-drive for errors and bad sectors, only minor stuff got fixed when running a check disk
- Checked CPU temperatures right after the crash and regular when running, it would never go above 50 degrees Celsius.
- GPU temperatures even lower temperature than the CPU
- Re-seating ram didn't work (there are two chips of 1GB each)
- Removed the battery to clear the CMOS
- Booting without:
- The back-fan connected
- CD- drive
- Front usb panel
- Hard drive
- Graphic card (an other one than I gave her because that one was transferred to her 'new' pc)
I postponed the research for a bit more than 2 months. And today I tried it again.
Unto my surprise the computed seemed to boot (I got to see the BIOS!!!). So I quickly entered the bios, checked the settings and monitored the temperature of the CPU.
Everything looked fine so I continued booting, I got the login screen of W7, entered the password and the computer froze on 'Welcome'.
I'm pretty much out of options and I suspect the motherboard, but I do not understand why it would work after being down for a few months.
The current computer state: I put the computer on and the 'busy' led indicates it does something, that is it. Nothing on the screen, no beeps about missing crucial hardware. I do hear the disk spinning up though, but I guess that is only because it gets power. I left it on for an hour to see if it just had gotten really slow, but it was still doing the same thing.
My question: What can be the cause of this weird behaviour and how to fix it?
Please leave a comment if something is unclear or more information is needed.
Solution: One of the ram chips wasn't 100% functioning. A classic hardware fault. However, I still would like to know, why it would work sometimes.