KT600-A/Sempron 2500 will not boot

These kinds of problems can be caused by a number of things, and you need to be methodical about narrowing down the possibilities.

- motherboard shorting on case
- CMOS jumper set to CLEAR, instead of NORMAL position
- bad connections
- faulty or inadequate power supply
- bad RAM
- faulty video card
- bad cpu
- bad motherboard

Procedure:
Take the motherboard out of the case and put it on a nonconducting surface, like wood or a cardboard box.
Install one stick of RAM, the cpu, and the video card, and reset the BIOS after installing the cpu.  Do not include hard
disks, other PCI cards, or other peripherals.

If it doesn't start up, swap the power supply.
If it still doesn't start up, swap the RAM.
If it still doesn't start up, swap the video card.
If it doesn't start up at this point, you may have a faulty cpu or motherboard.  The cpu can be tested by trying it in
another system; the motherboard really can't be tested, and you would point to it when everything else has been tested
out.

Well, I guess I will have to take it back to Fry's - don't have another vid card, nor power supply to test with. I did try the ram from the old mobo. By the way how do you determine if power supply is sufficient? I could not find any power requirement specs about this on ECS' website. If my power supply does prove to be inadequate I will buy one at Fry's.

KB

Figure out how much you need with this wattage calculator:
http://www.jscustompcs.com/power_supply/

To test the power supply, you can buy one of these:
http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=561263

or do it youself with a multimeter:
http://www.extremeoverclocking.com/articles/guides/Power_Supply_Guide_1.html

This problem is really twirling my cigar. Took motherboard back to fry's - it tested bad. Fry's hooked up replacement mobo with my CPU, video card and ram - it posted fine. Brought home the motherboard hooked it up out of the case on a cardboard box, same video card, CPU and ram - nothing on screen. Ok maybe bad VGA cable to monitor or bad monitor - connected monitor(using same VGA cable) to laptop and it is working fine. That only leaves the power supply; got out the multimeter and tested the 12v, 3.3v, and 5v lines from the back of the 20-pin ATX connector - all voltage tested good, well I don't have one of them fancy digital multimeters, just looking at a needle and numbers. Maybe a broken connector pin in the ATX connector? Took a ohm's continuity test from back to front of the connector pins - they are fine. What else could it be? BTW Callandor the info and links provided are excellent, thanks.

KB

This just in, I received a email from ECS support in regards to power requirments for this mobo and CPU. They suggest a good 400 watt power supply. Maybe that is the next step....

JPC 425 Watt power supply solved problem. Curious about the wattage calculator - it indicated I would need approx. 241 watts to power this system. Although I could not find my CPU I used the highest wattage CPU on list(77w).  So why wouldn't my old power supply have worked? I tried another wattage calculator from JPC http://www.justpcusa.com/support.htm. I used "high end" numbers and calculated about 325watts. Maybe the lesson learned here is when buying a power supply add 100 watts as a cushion when deciding power requirements.

KB

It isn't always a matter of total watts - if you have a lot of hard drives, for example, they will put a big drain on the +12v line when you start up, and a power supply's +12v line contributes only a fraction of the total wattage.