Well I am pretty stumped, I was testing "another computer" with my parts. I finished, put all my parts back together and turned on my PC, it booted up normaly. But I noticed that on the BOOT it said I had 1150mhz processor instead of 1800xp. Well this has happened to me before, so I got into the cpu voltages and it was on 100/100, I changed it to 133/133 reboot. Now computer will turn ON all light stay on solid, but I wont get a display or a beep, it will just stay on. This problem happened to me about 6 months ago on another similar computer 1200xp, the voltages were 100/100 I boosted them up too 133/133. I couldn't turn on the computer and had the same problem, I figured it was the voltages but couldn't get back into BIOS to change it. I took it too the place where I bought all the parts, and they took a look at it and told me I had the wrong voltages set and that is why it did that. Yet I never saw how were they ever actually got into the bios to change the voltages since it was black. I am pretty sure something similar has happend to my computer, but I don't know how to get into the bios to change the cpu voltage, since the display is all black and the pc wont even beep. If you can please help I would greatly appreciate it!

OK I am been trouble shooting this some more, so far I have removed the cmos battery and erased the cmos setting by moving a jumper, so they should be erased. NOTHING! still no reaction from PC. Then I dismantled the computer, taking everything out! only motherboard and Powersupply. I don't get any beeps, don't know if I should?? But the computer is acting a little bit normal, because now only the power on light is on, and I can actually reboot it and power it off from the front panel buttons. (I used to have to unplug the PC to shut it off) One thing I noticed when I with only the mobo and powersupply running, the PWSupplie's fan is running very very slow! don't know what this indicates. I put the CPU back on the motherboard, and turn it on, now I don't get any LED lights and can't reset or power it off. Same things happens when I only put one stick of 256 ddr memory 266mhz, without the cpu! I don't get ANY RESPONSE BACK FROM THE COMPUTER, from doing any of these things. It doesn't whine, beep, or anything! I am thinking that either the mobo or cpu is bad, I am leaning more towards the mobo. But it was working fine a couple of hours ago, I don't know what could have gone wrong. I am hoping there is some thing I might have overlooked, Need your expertise on this guys.

you may have fried something by toruning the voltage up.....

The 100/100 and 133/133 in the above posts are FSB frequency, not voltages. Regards.

Hold the page up button when you 1st hit the power button or clear the cmos with the cmos jumper.

I will try what Ben Rogers said and hold down the Page down button, I tried clearing the cmos by taking out the battery already and moving a certain jumper to clear it, but to no avail. This problem has freaked me out soo much that, I had dreams last night about it that I fixed it like 3 times and it kept breaking :) And I don't know if I fried it by changing the the setting to 133/133 because that was what the computer used to be, well I don't know anymore so I am willing to try anything.

Ok well I did I guess that last of my diagnosing, and well the holding Page up didn't do anything different, don't know what it is supposed to do. But I connected everything back how it was, and I noticed that when I turn on the PC all the led light stay solid and dont go out, even my cd-rom, and I can open or close the shuttle. But as soon as I take out the CPU I can actually hear the harddrive starting up, and I have 2 of them so I can really hear them hum in unison, all the LED's still stay on but I can now open the CD-rom shuttle, and I can power off the PC if I hold down the Power button. I am thinking it is the CPU, I hear the core's crack when trying to shimmy out a cpu fan, I remember doing that a bit so I don't know if that caused it. But I remember the PC turning on, and then me changing the value on the frequency or clock however you call it from 100/100 to 133/133 and that is when my computer didn't want to turn back on. Tomorrow I am taking it to the shop and pay don't know how much money to get it looked at over there. It is kind of embarresing, I am an MCSE and A+ certified and I can't figure out what is wrong with this thing!