I have checked for viruses in safe mode, also with networking and online scans...nothing. My bios has been reflashed and successfully updated, but problem remains, which is, if I set bios to any settings whatsoever...it will not boot. If I reset cmos with jumper, bios will boot at exactly the second attempt at startup every single time. Possible issues - did I overclock my processor. Possible. I have replaced motherboard battery. Do I have boot sector virus? Bios virus? Did I overheat motherboards by overclocking? When bios boots, it used to say 2400+. I think it should have been 1800+ and I may have been overclocking it. Now it boots to only 1000. Over the last year and a bit, computer, clock would reset along with changes in bios startup to 1800+. At the time I thought this was a virus, but was it my processor or motherboard changing my processor settings to what they should have been? New developments, fan in powersupply went a few months ago and I only replaced fan and not entire power supply; also, used partition magic 8.0 to make partitions in recently installed hard drive. And yes, I have checked that hds are installed properly via jumpers, etc.

First of all, I think you need to set up your processor in the BIOS correctly. I have the same proccessor as you, and from memory its a 2200+, not 2400+ at 1800MHZ. The Voltage should be 1.6/1.65 and the clock frequency 133MHz. (you normally can select either 100MHz or 133MHz). You won't notice the change until you reset and look at the BIOS again (it should display at the top somewhere 1800mhz). It may be because something in the BIOS is wrong, it keeps setting to failsafe defaults. IF this doesn't work, I'd worry that the flashing of the BIOS didn't go as smoothly as you planned and you may need to reflash it, although I'm not even sure if you can do that. You ask the manufacturers nicely if they can sort you out with a later version of the BIOS without any changes, just to trick the MO/BO into thinking its got a brand new BIOS. Anyway, you have enough the think about! :-) AMD Athlon 1.8GHz 512MB RAM 120GB HDD SATA 12GB HDD IDE GeForce 4 Ti4600 w/ 128MB RAM Pioneer DVD/RW SB Live! 5.1 ABIT NF-7S Mo/Bo

You have to clarify what CPU you have. The XP2400+ runs at 2000MHz (15 x 133MHz)...the XP1800+ runs at 1533MHz (11.5 x 133MHz)...& as marky81 pointed out, the XP2200+ runs at 1800MHz (13.5 x 133MHz). I'm assuming that the FSB has reset to 100MHz (200FSB) instead of 133MHz (266FSB). However, the problem with the above CPUs is that none of them would default to 1000MHz because none of them have a 10.0x multiplier. Is it possible that it's defaulting to 1150MHz instead of 1000MHz? That would make more sense. The Sempron 2400+ runs at 1667MHz & DOES have a 10.0x multiplier (10 x 166MHz). If the FSB was to default to 100MHz, that would put you at 1000MHz? The problem with that is your board doesn't support the Sempron so it would NEVER be recognized as an 1800+ or 2400+. That's because your board doesn't support 166MHz/333FSB. If you were to set the FSB to 133MHz with a 10x multi, the CPU would be recognized as a 1500+. Asus A7N8X-X 1800+ @ 8 x 210MHz 768MB PC3200 Asus A9550 128MB/128-bit Gamer Edition WinME/WinXP Pro

I flashed my biosm only last night and that happened to me, it defaulted to 100MHz instead of 133MHz, so it left the processor at some ludicrous speed. I opted for 'user defined' then changed it to 133MHz and got my processor speed right (back to 1800MHZ). AMD Athlon XP 1.8GHz 512MB RAM 120GB HDD SATA 12GB HDD IDE GeForce 4 Ti4600 w/ 128MB RAM Pioneer DVD/RW SB Live! 5.1 ABIT NF-7S Motherboard

If your CPU runs at 1800MHz, you have a 2200+, just like marky81 said Asus A7N8X-X 1800+ @ 8 x 210MHz 768MB PC3200 Asus A9550 128MB/128-bit Gamer Edition WinME/WinXP Pro

So, from your prompt replies, I am now sure that I have NOT overclocked my processor. I set it at 133 mhz (2400+) and with 100mhz (1800+) at what I thought then was the default settings. Since date was changed accompanying processor change to 100, I assumed it was a virus. So what would be causing my bios difficulties. To be clear, I reflashed bios to clear up this dilemma, so this behaviour precedes bios reflash. My floppy does not work saying "A:\is not accessible No ID address mark was found on the floppy disk." So what is going on? Is my processor just done, or motherboard? Bios virus? Any ideas to solve are appreciated

It sounds like the BIOS is corrupt somehow. You still haven't given us your motherboard model. Also, you have to be claer on this: your processor model is 2200+ NOT 2400+!!!! AMD Athlon XP 1.8GHz 512MB RAM 120GB HDD SATA 12GB HDD IDE GeForce 4 Ti4600 w/ 128MB RAM Pioneer DVD/RW SB Live! 5.1 ABIT NF-7S Motherboard