Inspiron 518 locked on startup

Hi Morecoabell5,

One been indicates a possible motherboard failure ("BIOS ROM checksum failure"). My first suggestion would be to try to reset the CMOS.

Clearing CMOS Settings 
1. Follow the procedures in Before You Begin. 
2. Remove the computer cover (see Removing the Computer Cover). 
3. Reset the current CMOS settings: 
a. Locate the 3-pin CMOS jumper (CLEAR CMOS) on the system board (see System Board Components). 
b. Remove the jumper plug from the CMOS jumper (CLEAR CMOS) pins 2 and 3. 
c. Place the jumper plug on the CMOS jumper (CLEAR CMOS) pins 1 and 2 and wait approximately five seconds. 
d. Remove the jumper plug and replace it on the CMOS jumper (CLEAR CMOS) pins 2 and 3. 
4. Replace the computer cover (see Replacing the Computer Cover). 
5. Connect your computer and devices to electrical outlets, and turn them on. 

Osprey - thanks for the suggestion.  I tried it but no change - same as before.   What now?  

Thanks again

If the motherboard has failed, you can swap in a third party replacement like this: www.newegg.com/.../Product.aspx

Great - how do I know if its the motherboard?   And if it is, what are the specs I'm trying to match with a replacement?

Thanks!

If the power supply has been replaced yet on bootup one beep results, that suggests the motherboard has an issue.

It's a Socket LGA775 and the chassis has a removable IO shield, so the third-party board I linked to should fit. You also have the option of updating to a Socket LGA1155 board, but you'd also need a new CPU and memory.

New mobo on the way - many thanks to all

If the new motherboard fixes the problem, could you do us a favor and mark the thread as answered?

Great -- we're looking forward to hear that all is well again with your 518!

Yes, will do - thanks again