Computer boots up to blank screen

[CReM@$TeR]

Help!
Today, I came home from work, and the screen saver was frozen. No ctrl-alt-del out, nothing would work except to reset it. On boot up the computer would not even get to a bios screen. Usually the first thing to come up is the video card stats, then the bios. I get nothing. No series of beeps, just a hard drive light that stays on for about 10-15 seconds, then goes out. Any ideas? I did replace the Hard drive about 4 days ago, since the old one crashed. The video card was replaced 4 months ago, because the other fried. What now? Thanks.

P. S. - System stats:
AMD 1.2GHz Athlon
IBM Deskstar 80GB 7200rpm HD
256 MB RAM
NVidia GeForce 2 MX400 64meg Video card
ASUS A7V133/SWA motherboard.

[enat66]

Was anyone on your computer, if they did ,did they attempt to flash the bios or somethign similar. Also check inside the computer to see if anything got knocked loose. Oh..Maybe the screen is black cause the video card or moniter broke, see if you can't borrow a friends for a day and try it to see if thats the problem.

[jtdoom]

Hi

I have this gutfeeling about this
I could be wrong, but i think you have a power supply issue

what make of case and power supply is this?
what brand/model power supply?
overall total wattage?
wattage on +5Vsb
total max combined on 5V and 12V

I can tell you that a forty dollar case that came with power supply is a risk.
a reasonably good quality PSU can cost you around $50

======
another note
because computers and displays are a fire hazard, it's not too smart to leave a computer running unattended

[CReM@$TeR]

JTDoom,
I think you may be right, I have noticed that the fan for the power supply does not come on when I power up. The rest of the case fans do. I got out my motherboard book, it says if I don't have a minimum of ten milliamps to the 5V standby wire going to the board that I may experience startup problems. I only have about 3mA. I'm in the process of trying another powersupply from another computer I have. The power supply is a HeraIchi Electronic Corp. HEC-250AR, 250W. What made you think it was the power supply?

[CReM@$TeR]

Well,
I tried the other power supply, and no luck, it did however read 14mA at the 5V standby instead of only 3mA. This time however, something weird happened, immediately when I plug in the motherboard, and turn on the main power supply, the computer starts up, it doesn't wait for me to hit the case power switch. I'm wondering if the motherboard is damaged. the reset switch doesn't work, and the HD LED doesn't work anymore, yet they are all plugged in. AAAAAGGGGHHHH!

[Alfons]

You should remove the front panel connections to see if the front panel momentary-on switch is permanently in the ON position or if it's a Power Supply fault. I would test this switch with a multi-meter and not with the PS. If the switch is good then I wouldn't use that PS because there may be a lot more wrong with it than just the power-on circuitry. It could also be a Motherboard fault but you should try it with a PS that you know FOR SURE works properly.

[enat66]

Just to let you know my computer always turns on like that when I turn off and on the power supply switch. And my computer seems to work fine.

[jtdoom]

Hi again

I think you proved to yourself that +5Vsb was too weak

when the other Power Supply Unit - PSU for short- was connected, it powered up.

here is what I think happened
the machine went into standby
you could not wake it up (flipflop did not flip on)

when the power went cold (while switching out the PSU) this flipflop could reset (they can do that)
(in more difficult cases, one may have to use the reset CMOS jumper as well.)

note; when you reset CMOS, you have to get into BIOS afterward
(where you set time and date, and other user settings like boot order and BIOS support for power management)

anyway, with a better PSU, you can test the standby feature again.
(note that all hardware has to be ACPI compliant)
=====

now, why did it fully power up ?
that is a BIOS setting (stored in CMOS)
look for something that says "after power fail" or similar
I usually set this to "stay OFF" rather than "last state"

=====
as for the switches and LEDs, Alfons already said that better than I can

[rogeroo]

Don't know if this helps but did you by any chance update the video drivers to the latest detonator drivers?I have the same video card and when i installed the newest drivers sometimes when i boot the computer all i get is a blank screen(don't know why).When i uninstalled the drivers everything was ok again.