[SOLVED] Gateway fails to boot, all troubleshooting steps attempted

[RockmanZ3R0]

Hey hey, I recently started refurbishing an old Gateway Essential and was pleased to find everything looked pretty darn good inside, no bulging caps or corrosion. When I first tried to plug it in, it automatically turned itself on. I followed all the steps to fix this like a new battery, changed bios settings from wake on lan, etc. It persisted until I let it fully boot into 98 and then did a shutdown. It never did it again.

Today I was working on installing software that I wanted to have on the drive. I stepped away for 10 minutes and when I got back the screen said no signal and the mouse, keyboard did not do anything. So, being the only thing I could think to do next I did a hard shutdown with the power button. Waited a few seconds and then turned it back on. But it never came back on.

The main power light will come on, the hard drive light will come on for 10 seconds roughly then turn off. No error code beeps, just fans.

I tried re-seating the memory, video and sound cards. I removed everything and tried, got an error code beep for the missing video card. Plugged everything back in, tried a new hard drive. Nothing works. It just sits there blank and not booting up.

Other forum posts seem to suggest similar problems being related to the motherboard or the power supply but I was hoping someone could shed some insight into what to try next in troubleshooting this problem, I do not have any spare parts lying around to try unfortunately. Thanks!

From what I was able to glean from control panel and other menus it has,
Gateway lp mini tower tb3 essential 700
NVIDIA TNT2 64 video card
384MB ram, unsure of what kind.
Pentium 3 700mhz processor (unsure of generation, build)
10gb hard drive
Iomega zip drive
3.5" 1.44 HD Floppy (Does not work)
Some generic sound card which also has a cable leading to a DVD ROM drive.
The monitor im using is a insignia flat screen, worked well all things considered.
Software that was added - Microsoft Encarta 98, Unreal Tournament GOTY, 3D Movie maker.

 

[RockmanZ3R0]

Adding to this. Today I tried to remove the CMOS battery, discharged whatever was remaining by holding the power button and then plugged the battery back in. Immediately the computer returned to the same ol shenanigans of turning on as soon as it is plugged back in.

I cannot enter the BIOS screen at all, no keys work (Num lock etc do not light up)

 

[RockmanZ3R0]

I finally recieved in a brand new power supply and got it installed. This time when I tried to turn on the computer it sounded like it was turning everything on, the HDD spun up, there was whirring, however still no signal, no beeps. However this time the light next to the On light remains on as well instead of turning off after 10 seconds.
The DVD-Rom drive will open and close.

 

[RockmanZ3R0]

At this point I received a new (used) video card that was tested prior to shipment. Plugged it in and I still have the same issue. Any thoughts people? At this point i've practically replaced everything inside except the motherboard. However, when I removed all the ram to reseat it one final time. The mobo did let out a series of beeps when nothing was in it. Is it possible the mobo will still beep even if it is not working? What should I try next?

 

[hang-the-9]

At this point I received a new (used) video card that was tested prior to shipment. Plugged it in and I still have the same issue. Any thoughts people? At this point i've practically replaced everything inside except the motherboard. However, when I removed all the ram to reseat it one final time. The mobo did let out a series of beeps when nothing was in it. Is it possible the mobo will still beep even if it is not working? What should I try next?

Could be motherboard, could be the RAM also since you did not test it with another known good stick. Did you test it with one RAM stick at a time? Motherboard or power supply would be my top two guesses about where the issue is.