Niezgodka wrote on 2021-12-05, 20:08:

Sorry for microwaving such an old thread, but I have 433 LV. It works, but once or twice it died on me (no display, keyboard bli […]
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Sorry for microwaving such an old thread, but I have 433 LV. It works, but once or twice it died on me (no display, keyboard blinks, fan spins). Not sure why 🙁
PSU seems to have different markings (it is p4 and p5), and I'm not sure if I can plug regular P8 and p9 connector into it.
Question, can you upgrade its CPU with just sliding 486DX2 or DX4?
Also, does anybody know how to get to bios in it?

I have an old Optiplex 466-L here that I plan to clean up. I don't remember where I found this, but my notes say that to get into BIOS this _should_ work:
At boot, hit Ctrl+Alt+Enter, then it prompts for F2

Intel486dx33 wrote on 2018-08-29, 21:30:

Restoring an old Dell Optiplex 433/L ( Intel 486dx-33) […]
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Restoring an old Dell Optiplex 433/L ( Intel 486dx-33)

I worked on this before and I think I might have shorted something out messing around with the IDE cables and sound card.

I get NO video. It use to work. Video was working fine before. But now I get no video.
I tried an ISA video card but still no video.

I disconnected all the IDE/Floppy ribbons and removed the ram, but still no video.
It does not even beep and error codes.
I see the keyboard lights work on power up.
but I don't think it is posting as I don't hear any beeps.

I could not find a manual on this computer.

The motherboard does have silkscreen labels for the jumper settings.
I reset the bios and tried to disable the onboard video and use an ISA video card. but no luck.
I put a NEW battery in it.

Do you think something is shorted on the motherboard ?

It sounds like it is booting when I turn it on.
I hear the drive spin up and reading.
power supply and power switch appear to be good and working.

What do you think ?

I just got a DELL 433/L from eBay that worked for the seller but for me I've got the same issue that you wrote about (i.e. seemingly boots, but no video). Did you find the cause or solution? I know it has been a long time for you, but I hope to get some feedback so I can use this new/old PC. Thanks!

Grab a POST card and see if it gives you any signs of life.. that's a starting point.