Gateway GT5240E pc no screen?

[mikehende]

This Gateway pc powers on, fan is running very high I think and no screen, I disconnected HDD and Optical drive, reseated Ram, same problem, help? Other problem is as soon as I plug in power cord, pc turns on without myself having to press the power button on the front of unit as normal

[GCWesq]

Are you collecting broken down computers?
Do you get a POST beep on booting (with or without HDD)?
Does it turn off when you press the Power button, or do you have to turn it off at the wall outlet?
I'm just wondering if there's a problem with the power switch, and that's upsetting everything else.

[mikehende]

No, these 2 pc's belong to a friend of mine. Yes, it powers off when power button is pressed, I took off ram, no beeps. Strange though, I don't see a light on on the mobo, also, with the power supply plugged in, there are still 4 slots empty on the mobo's connector, I can't see any reason why the factory would make a system where the PSU connector is 4 holes or slots short of the mobo's power connector? In other words, the mobo power connector has 24 holes and the PSU connector has only 20 plugs or whatever you call it so it's 4 plugs short of the mobo connector.

[GCWesq]

Getting very suspicious here. Do you know anything about the history of this PC? Could it have the wrong sort of power supply? Has it ever been changed?
There should be lots of beeping if you try to start it up without RAM.

[mikehende]

I have no idea, I guess I will have to call Gateway to find out about the PSU issue, I am guessing the mobo is dead also?

[GCWesq]

Dead MOBO might be the problem, but there are other possibilities.
This might be of interest:

Newer Pentium 4 motherboards, like the one we used for the Socket 775 Pentium 4 in the 4th edition of Build Your Own PC, may have a 24 pin eATX connector instead of the standard 20 pin connector. However, they are usually designed so you can still use a standard ATX power supply with a 20 pin connector and just leave 4 of the pins unmated, and the socket should still be keyed so the connector can only go in on the right side. However, the presence of a 24 pin connector is telling you that the motherboard has a high power requirement, and you'll probably have the option to attach another 4x1 drive connector to supplement power. Also, make sure you take advantage of any power connectors direct to video cards, which reduces the motherboard load.

Is it plugged into the right holes (maybe it only goes one way, but you should check)?
Is there an additional 4-pin plug for extra power?
Is there enough power for the PC?

[mikehende]

There is no extra 4 pin plug. The PSU only goes in one way so your reference regarding the 20 vs 24 pin issue explains that. I think the mobo is dead but how can I tell for sure?

[GCWesq]

Best way is to remove everything not needed for a POST and try it. Remove RAM, CPU, etc. You should still get a signal on the monitor.
Before that, try resetting the CMOS. You can do this by removing the CMOS battery (a flat battery on the motherboard about 2 cm or three quarters of an inch in diameter - turn the power off AT THE SWITCH FIRST) for about 5 to 10 minutes, then replacing it.
Or you might be able to find jumpers on the motherboard that say Reset CMOS or Clear CMOS or something like that. You have to change those jumpers - they might tell you how on the motherboard (usually from 1 and 2 to 2 and 3), push the power button once, wait a minute, then change the jumpers back.
Of course it might be the power supply again, or it might be a dead CMOS battery. Can you try another one?

[mikehende]

resetting the cmos battery didn't help, I don't tried a battery from another pc, same problem.

[GCWesq]

Hmmm... Best try checking out the motherboard then, or see if you can try a different power supply.

[mikehende]

tried a different working PSU, same deal so it's either mobo or processor.

[GCWesq]

Unlikely to be the processor. A faulty processor shouldn't stop the BIOS booting (with a POST beep).
Anyway, you can test it by removing the processor. You should still get the beep.

[mikehende]

Well, I think we've narrowed this down to the mobo, thanks for helping me diagnose!

[GCWesq]

Glad to help.
Sorry about outcome.
I'm not sure I'd jump just yet, though. Someone else seeing this might have some other ideas.
It did occur to me that the BIOS software might need updating, but I can't see how you could do that if it won't boot.