Bad Power Supply. Weak Voltage power rail.
Not enough power to turn the Processor on, and keep it on.
1) ALL those LED lights together, use less than 1 Watt of power.
2) EACH fan uses 2 to 3 Watts
3) A typical Processor can use 51 to 125 Watts. Depends on what Processor it is. (Older Processors use less Wattage)
The Compaq Presario SR1810NX desktop computer, comes with an AMD Sempron 3200+, processor.
(Uses the Socket 939 processor socket)
[Maximum operating capability is a 1.8GigaHertz frequency rate.
Giga = Approximately 1 Billion
Hertz stands for Cycles per Second.
Frequency Rate is correct computer speak for 'Speed'
The AMD Sempron 3200+ processor, can operate at a maximum frequency rate of 1.8 Billion Cycles per Second ]
HP Support >Compaq Presario SR1810NX desktop computer > Product Information > Product Specifications,http://h10025.www1.hp.com/ewfrf/wc/document?docname=c00609384&tmp_task=prodinfoCategory&lc=en&dlc=en&cc=us&product=1841795&lang=en
The AMD Sempron 3200+, can use up to 62 Watts,http://en.wikipedia.org/wiki/List_of_AMD_Sempron_microprocessors#.22Palermo.22_.28Socket_939.2C_E3_.26_E6.2C_90_nm.29
When you press the plastic Power On button, you are contacting a Power On switch inside it.
(Typical ATX Power On switch,http://www.directron.com/atxswitch.html
When an ATX power supply is plugged into power, there is a 5 Volt Standby power, present inside the power supply.
Pressing the momentary contact power on switch, closes a circuit that directs the 5 Volt Standby power to 'excite' the power supply, and turn it on.
The first chip to receive power is the BIOS chip.
[Chip and Chipset are slang terms for I.C.
BIOS stands for Basic Input/Output System]
BIOS looks to see what devices are installed, does a Ram Memory count, TURNS the Processor on, and hands the computer over to the Operating System.
(Windows XP is one example of an O/S. Operating System)
The LED lights receive power, so do the fans, and the Harddrive. When it's time for the Processor to kick on, there isn't enough power, and the Power Supply 'falls to it's knees'.
Replace the Power Supply.
It's just one of the basic ATX power supply's that are readily available in a multitude of places.
The Wattage is 300 Watts.
The ATX form factor for this power supply, (Size and shape), is approximately 6 inches Long, 6 inches Wide, and 3-1/2 inches Tall.
Power cables needed:
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