Installing a new CPU

Question

I have a km2m combo motherboard that supposedly supports a XP 2400 CPU. I'm trying o install, but it wont even power up, and when I try putting the old cpu back in it boots for about 15 seconds and then shuts off.
Please Help

Answer 1

I purchased a new UPS for my system (just in case) Ehat do you all think of this!!!
Feature:
ª Complies with INTEL® ATX 12V standard
ª Complies with FCC part 15 subpart J class B 115 VAC operation and CISPR 22
ª High efficiency output
ª Two 12VDC fans (one with 4 blue LEDs)
ª MTBF over 30,000 hours at 25° C
ª Output short circuit protection (except +5VSB)
ª Output over voltage protection  
ª Output over wattage protection (570W)
ª Resettable power shut down
Specification:
ª Maximum output: 450W
ª Dimension: 5.9"(L) x 5.5"(W) x 3.4"(H)
ª Working Temperature:  0° C ~ 50° C
ª Input voltage: 115VAC / 230VAC
ª Input frequency: 47Hz ~ 63Hz
ª Storage and shipping Temp:  -40° C ~ 55° C
ª Humidity: 20% ~ 80%
ª Response: Less than 1 ms
ª Dielectric Withstand: Input to frame ground 1500VAC for 60 seconds
Output Characteristics:
Output Voltage Min. Output Voltage Max. Output Voltage Min. Load Current Max. Load Current Max. Ripple & Noise
+3.3V +3.16V +3.46V 1.0A 28.00A 80mV p-p
+5V +4.75V +5.25V 2.0A 34.00A 80mV p-p
+12V +11.4V +12.60V 0.5A 14.00A 100mV p-p
-12V -10.80V -13.20V 0.1A 0.8A 100mV p-p
-5V -4.50V -5.50V 0.1A 0.5A 100mV p-p
+5V Standby  +4.80V +5.25V 0.0A 2.0A 50mV p-p