I have an HP Compaq PC. A d530s running Windows XP Professional. When I turn the PC on, the power light flashes red 4 times (1 red flash per second). Pauses ~3 seconds and repeats the red flashing. Just trying to find out what problem that indicates.

Hi:
Here is what I would do...
Turn the PC off and unplug it. Then press the power button to drain any residual power from the motherboard.
1. Remove and reseat the memory module(s). Restart the PC.
2. If removing and reseating the memory module(s) doesn't work, if you have more than one memory module installed, remove all but one, and start the PC.
Test each memory module one at a time, until you find the one that is bad.
If none of that works, check for bulging and leaking capacitors on the motherboard. These may be particularly noticeable around the processor area.

According to the troubleshooting guide for this model, the red light flashing five times indicates a problem in the RAM (memory), before the video subsystem is ready. You may just need to open the case and make sure the memory sticks are fully locked in their slots. If you just added new memory, it might not match the required specs.

Blank screen and the power LED flashes Red five times, once every second, followed by a two second pause, and the computer beeps five times. (Beeps stop after fifth iteration but LEDs continue flashing.)

Cause Pre-video memory error.

Solution
1. Reseat DIMMs. Power on the system.

2. Replace DIMMs one at a time to isolate the faulty module.

3. Replace third-party memory with HP memory.
4. Replace the system board.

http://bizsupport1.austin.hp.com/bc/docs/support/SupportManual/c01363877/c01363877.pdf

what it might be is that your hardrive or power supply is not working and that you need to have it replaced

soory i couldnt be of more help!!

Do you have a windows XP cd?
If so you can try booting from the cd and running recovery console.
from recovery console type chkdsk -r
This should repair any bad sectors on your drive, allowing the drive to boot
(this scan may take some time)

4 beeps & 4 flashes mean problem with the power supply. For my experience, most of the time the PSU is good, it is just overloaded.

For more LED and Beep messages, check this link:

http://bizsupport2.austin.hp.com/bc/docs/support/SupportManual/c00067072/c00067072.pdf

If the bottom light flashes red 4 times then repeats itself the power supply is defective.

pls try to use another compatible memory stick.

then confirm the status of your micro processor

System does not power on and the LEDs on the front of the computer are not flashing.
System unable to power on.
Press and hold the power button for less than 4 seconds. If the hard drive LED turns green, then:
1.Check that the voltage selector is set to the appropriate voltage.
2.Remove the expansion cards one at a time until the 3.3 V_aux light on the system board turns on.
3.Replace the system board.
OR
Press and hold the power button for less than 4 seconds. If the hard drive LED does not turn on green then:
1.Check that the unit is plugged into a working AC outlet.
2.Open hood and check that the power button harness is properly connected to the system board.
3.Check that both power supply cables are properly connected to the system board.
4.If the 3.3 V_aux light on the system board is on, then replace the power button harness.
5.If the 3.3 V_aux light on the system board is off, then replace the power supply.
6.Replace the system board.

Here is what is says in the owners manual in what to do in this case, Hope this is a Help, Happy Holidays
Red Power LED
flashes five times,
once every second,
followed by a two
second pause.
5 Pre-video memory
error.
1. Reseat DIMMs. Power on the
system.
2. Replace DIMMs one at a time to
isolate the faulty module.
3. Replace third-party memory with
HP memory.
4. Replace the system board.
Red Power LED
flashes six times,
once every second,
followed by a two
second pause.
6 Pre-video graphics
error.
For systems with a graphics card:
1. Reseat the graphics card. Power on
If you need anymore let me know and I will post them for you.

it all depends on the number of flashes , pause, repeat.
Since the problem did not indicate any beeps her is the following info


Power LED blinks RED 2 times, one every second, followed by a
2-second pause. = Processor Thermal Protection Activated


3 blinks 1 second apart = Processor not installed (not an indicator for a bad processor).

4 blinks 1 second apart .= Power Failure (power supply is overloaded)

Other possibilities are:
5 blinks 1 second apart No memory
6 blinks 1 second apart No graphics
7 blinks 1 second apart System board failure (detected prior to video)
8 blinks 1 second apart Invalid ROM