Green light flashing on compaq presario - computer will not turn on

SOURCE: Compaq Presario v5000 won't turn on

If the laptop posts: (power on self test) and you see stuff on the screen, no matter how short ,do the following:
if you have a bootable anti virus disc use it to check for any viruses , if not
try a recovery disc,
both will try to access the hard drive.
if they do not work,(nothing has changed) nothing comes on the screen.
laptop does not post:
remove the screw(s) holding the cover plate where the ram lives
remove the memory sticks, clean the gold edges with a pencil eraser both sides and re-insert them, (not an ink eraser as it will do damage)
swap them around if you have more than one,
if you only have one, borrow one from a friend or try the ram in your friends laptop ,if that's possible, or take the ram to your local pc shop and ask them to check it for you (they may or may not do that for you)
if you can establish that the ram is ok, and anti virus and recovery disc's do not work,then it is most likely, the motherboard has failed .
good luck with that and let me know how you get on.
Terry

SOURCE: Desktop shutdown. will not come back on. Green light flashing.

This sounds like it might be a power supply problem. If you are tech savvy enough you can do this. 1st try unplugging it, let all the lights go out and then plug it back in. Try to turn it on. It might work. If not, unplug the pc and hit the power button to discharge all voltages. Open the side panel and watch where all the cables go. Label if needed. Unplug all cables carefully. The ones on the motherboard have a clasp that holds them. You simply sqweeze the clasp and it should pull free. After all cords are removed, remove the screws from that hold the power supply itself in. These are usually on the back. Pull the power supply out carefully. Take the unit to your local computer store. They should have a tester to test a make sure that it works ok. Replace if necessary. If it is not the power supply you might try only plugging in the motherboard and HDD. Remove and boards using a static strap between you and a grounded (plain metal) on the case. after that, plug the unit in and see if it powers up. If it doesn't, it could be the motherboard or a video board you needed to keep plugged in.

SOURCE: Power light flashes and computer turns off

This is a 1,2,3 item. If it is not the power supply, the cpu or motherboard are the next likely culprits. Generally, if the power supply is OK, the pc would have the fans running and you should be able to open the case and check the North Bridge, the large chip on the motherboard near the cpu and the cooler on the cpu itself. If they are both still cold, it is most likely the mother board.
It it were the cpu, it won't post, but you should still be able to feel the heat with the back of your fingers, just to be safe and touch it quickly so you don't get burned.
You can also try to remove the ram and try to reboot, if you get a steady series of beeps, you can add 1 stick at a time and reboot just to try to elimanate ram as a potential problem.
My next step would be to remove all of the other cards and add 1 at a time and reboot after each card, I probably removw the 4 pin connectord from the dvd/cd hard drives also ans add 1 at a time.
I know this sounds like a lot of work, but this is how I troubleshoot pc and telephone systems for the last 25 years.

pankaj rautela

• 1252 Answers
• Posted on Sep 17, 2009

SOURCE: Compaq Presario SR1650NX will only

DO one thing remove the RAM from the slot , then insert it again, then check

joecoolvette

• 5660 Answers
• Posted on Jun 29, 2010

SOURCE: compaq presario S0000/8000 won't turn on. Green

No, I would approach it a different way, with the diagnostic LED's that are blinking.

Indication is that the Power Supply has a weak Voltage power rail. If you test the 12 Volt power rail, I think you'll find it's less than 11 Volts.
(11 to 13 is okay. Less than 11 requires a Power Supply replacement)

You can test with an economical multimeter, (Usually $5 to $12), or an economical power supply tester.

One example, http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=5250576&CatId=5471

Or, you can substitute the power supply in the computer now, with a KNOWN to be Good, Compatible power supply, for a test unit.

[Compatible being:
1) Right size and shape of case. The cas is approximately 6 inches Long, 6 inches Wide, and 3-1/2 inches Tall.
It is an ATX style of Power Supply.

2.Has the correct power cables, and the correct amount of power cables. If there are more power cables than needed, they are tied up out of the way with zip ties ]

May sound a little far fetched, but I have known people to have computers with a KNOWN to be good Power Supply, that are sitting around, and no longer being used. The Power Supply is borrowed for a test unit.

Generally, the cause of computer failure can be attributed to the inside of the computer, and the inside of the Power Supply is dirty.

The Power Supply has two cooling components.
One being the Fan, the other are Heatsink's used inside the Power Supply.

http://en.wikipedia.org/wiki/Switched-mode_power_supply

Once the cooling components are coated with gunk, the cooling capacity drops tremendously.
Heat = Wasted Energy

The more heat, the more the Power Supply strains to keep up with the call for power.
Eventually components inside the Power Supply fail, and the Power Supply fails.

The second cause of Power Supply failure is that it is a low quality unit, and low quality components are used inside.

Next are Power Surges, lightning strikes, and brownouts.

To summerize:
I believe you'll find you have a bad Power Supply.
If you wish to test it with a multimeter simply state in a Comment.
(Upper right of your page)

If you wish help in finding a replacement unit, also let me know.