I upgraded the RAM in this CPU. When I attempted to reboot after the upgrade, I received the following, "System32\Drivers\pci.sys missing or corrupt etc ..." I did some key board dances and the CPU told me to use Set Up CD, to possibly fix, pressing "r" etc ... HISTORY:A few months ago, I fixed a XP Home/S-2 CPU for a person; I used my XP CD in that repair. I must have left it, in that CPU, as I do not have. Person has moved away; phone disconnected. I called MS, and they were no help, and I understand their position. My trouble is, I have many things stored on my XP Home S-2. As we all think, I was not anticipating a failure with a simple RAM upgrade, so much data was not backed up. It happened. DONE THUS FAR:I have read notes in this site; but I DO NOT have the Setup CD;I have attempted to COPY PCI.SYS to my XP C's Drive, it did not work, or I did not do it correctly. I am stuck, clueless as how to fix. I will be very grateful to anyone out there whom can provide me a solution. I know that I can purchase a new XP Home CD, but it will need a clean drive for the new install, and I will loose what I need on the drive the way it is currently. Can anyone help me to relight this XP Home S-2 CPU? Mike murzo1@aol.com I am just a hack.

best to get/borrow another harddrive, and install windows. then, set the drive with the data you want to save, the jumper to slave. then copy over the files pics you want to save. or use a flash drive to do that.

Try reseating memory and any pci adapter cards. Also, enter the Bios to ensure the memory is properly detected there and save any changes. Are you able to boot into safe mode? What happens when you remove the newly installed RAM?

Restore the RAM to the way it was before the upgrade. You might have got a defective stick.

Reply to Resp 3: I wrote earlier, but I have not seen my reply, so I am sending again. Your suggestion to restore the RAM the way it was, did the trick, and restored my XP CPU! Thank you very much, I would not have thought of that idea on my own. I have two additional questions: 1.] Can you or any other readers advice me on how, and where from, to download necessary data from this XP HOME CPU, so if I would encounter another failure, I will be able to relight the CPU. As I wrote earlier, I no longer have my XP HOME Set Up Cd, it is lost. 2.] This question deals with New XP Home Cd's. In the height of my issue with this XP HOME CPU failure, I was talking with local retailers about purchasing a New XP HOME CD. They told me, the only way to repair my computer was complete reinstall, with a New XP CD. Is this true? Are these replacement XP HOME CD's only good for one install, and connot be used to fix or upgrade many CLU's as I have doNe with WIN98SE, and WIN 2000? Thank all of you that helped me solve the issue with my XP HOME CPU. Mike murzo1@aol.com I am just a hack.