Not sure this one goes under this category. If not, please move to the right cat.
I have that PC with an ASUS P5B mobo, core 2 duo E6600 CPU. It was running fine in a P150 ANTEC case with 450W PSU. I moved it to another case that has a 400W PSU. After I reassembled it in the new case, the computer would turn on (fans spin, HDD spins) but nothing would show on the screen, and there are no beeps.
However if i removed the 2 RAM sticks, i get long beeps. I tried another graphics card, same thing.
I tried to remove and put back the CMOS battery, nothing changes.
I tried all kinds of RAM combinations, nothing changes
One particular detail that caught my attention is the CPU fan. It starts at a certain speed, then after like 4 seconds it spins faster. Someone else posted about this same problem on another forum, but didnt bring any solution.
Could it be that my CPU is burnt out?
Or is the power supply weaker than it should be? (although I was reassured it was more than enough)
well the new case I got came with a new PSU of 400W
I will try to get a more powerful PSU, however I'd like to know if it the CPU that's caput. does the CPU fan speed thingy mean anything? (the thing in bold in my original thread)
I'm writing to tell you that the problem was SOLVED!
Well, it's a weird problem that someone else had with the same mobo, as I read on another forum...
When the PC is unplugged or power supply is turned off, when you try to turn it on again u'll get nothing on the screen... You will need to remove the memory stick(s) you have, put in another stick and then turn it on... You'll get a message saying that the CMOS settings are wrong... You'll go into the BIOS and configure the date and time, only then will you be able to replace your original RAMs and boot up normally...
Weird problem... I dont know if it happens with other mobos as well... It never happened to me anyway... and I'm not sure if this is related to a problem with the battery of the mobo... as when power is cut from the PC even if it's for a few seconds, something gets messed up in the CMOS...
Dont go running off buying a power supply. Jumbo's answer above (March 28, 2012) caused me to try removing all but one of my RAM cards. I had 4. This old machine had been off for many months, it booted up at first, then I poked a finger inside to move a wire so I cold read the mother board type, and it went blue screen. Sometimes just shutting them down and removing and reseating all that PCI cards and cable connectors to the MB will do it. That didnt work. But with only one RAM board in it booted right up. So I put in a second one in the slot it came from, and it would not boot. So I skipped a slot and replaced a second board in the slot it had been in, and it booted up. At that point I had enough to get to work ...So I still have one more RAM board to return to its original slot (not that it should matter). I think I had one bad RAM board, probably a cold solder joint because this machine had hung up mysteriously before. So --- try playing with the memory cards and connectors before buying a new PSU.