NEC PowerMate V100-no POST

[soupy1951]

My old faithful V100 with a P150 chip and 64 meg RAM and 1.6gb drive has quit POSTing. No beeps what so ever and only an NEC splash screen. It has a Benchmarq 3287 AMT RTC chip and I get no voltage across pins 1 and 24. The machine is stripped with only base memory, P150 CPU and onboard video hooked up. I get the NEC splash screen, the keyboard flickers for a second and if I hold F2 as power button is pushed I get the CPU ID screen and a patial memory count then no more keyboard response. It shows to push F2 for setup but there is no keyboard input happening. Is the Motherboard dead or is the RTC chip dead? I know this is an old machine but the challenge of troubleshooting things is what I enjoy. Anyone want to help out a nut with an old machine?

[Budfred]

Welcome to http://www.pcguide.com/ubb/pcgubb.gif

From your description, I am wondering if the power supply is shot. This is actually more likely than the other components and it sounds like you aren't really getting power to the board. If you are getting anything on the video, you are getting past POST since the video won't start without it. This means your speaker is either shot or not powered. I don't know what you are referring to with RTC?

[Sylvander]

Hello soupy.

If you send me a personal message enclosing an e-mail address I’ll send you a copy of my diagnostic charts for troubleshooting and a couple of documents about the boot sequence.

From the charts:

START UP TEST
1. Is the PC dead? No.
2. Did POST appear to run? No.
3. Were there any audible beeps? No.
4. The Power-On Self-Test failed to complete. [NO POST]

NO POST
1. Are the PSU voltages correct? Check them if you can. If they are not you may have a faulty PSU. Assuming they ARE ok then:
2. Disconnect all peripherals and system adaptor cards except the keyboard and video card/monitor.
3. Does the POST now run? If it doesn’t then your system board [or something on it (video card, CPU, memory)] is faulty. If it does run then:
4. Re-connect the floppy disk drive and run advanced diagnostic software from a floppy disk. Get “TuffTest-Lit” from http://www.tufftest.com/free.htm or better if you can. This is simple and basic.
5. Does the system board pass? If not then it is faulty. If it does pass then:
6. Switch of and re-connect ONE peripheral/adaptor card.
7. Does POST now run? If it doesn’t this last device connected is faulty and should be disconnected. If it does run the device should be tested using the diagnostics and if it fails is faulty and should be disconnected. If it passes it's ok and should be included.
8. Repeat from step 6 until all devices are tested, all faulty are excluded and all working are included, then re-test the system.

It all depends upon the symptoms and it’s better to have the charts, the boot sequence document and the offending PC before you.