All "drives" such as floppy, HDD, and optical usually have +12V and +5V and 3.784 is well outside a generous 10% tolerance.
At 10 years old, we are well past the usual 5 year design life so consider some new PSU but only after inspecting all boards for BAD CAPS. BAD CAPS on google.com gives you the story, pictures and what to look for.
Bob
I have an old Gateway mini-tower, model # MFATXSTL ELP 500L-2, manufacture date 12/22/2011.
Was running two days ago, when it suddenly shut down ten minutes after startup, power-on yielded yellow power button light (steady yellow), no beep codes, no monitor display.
Did the usual, reseated the memory cards, video card, rechecked molex connections and reseated.
Noticed when computer should have been running POST, floppy drive light did not come on. CD-ROM drive lights both flashed. fans for PSU and CPU ran, green light on motherboard.
Removed power lead to floppy drive, and system completed POST, reset BIOS to current date and time (put in a new CMOS battery just prior) and was able to boot to Ubuntu Linux 10.0.04 LTS.
System specs:
P4 1.5 gHz, 512 GB RAM, AGP 4x nvidia MX 200 card, integrated sound, integrated network card. Use a PS2 mouse and USB keyboard.
Was running this system and detailing steps to troubleshoot here when system froze completely. Forced shutdown gave green power button but did not complete POST as no video came up.
Now using another system to complete and finish this post.
Digital voltmeter with all power leads to peripheral drives disconnected showed 11.758 volts to mains, and 3.784 volts to floppy drive. Is this right? I did not check the main power to the motherboard.
I'm thinking the PSU is degraded, and will no longer supply enough current and wattage to run the system continuously anymore. System ran for about 40 minutes today before it locked up.
System was running two IDE HDD, two CD-ROM. Second HDD is used to backup data on the primary drive.
Also noticed when forced shutdown is made, system does not shut down immediately when it should be running POST as it usually does only two or three seconds in. It acts as if the OS is loaded when it cannot be after such a short time.
Appreciate any help

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