PCI System Management Bus Dimension 4100--Very perplexing

I helped friends with their DeLL Dimension 4100 Service Tag H1K7401, 800mhz P3, Bios ver. A11. All original except 2 sticks of 256mb Ram from Crucial. They had a Press Del to Continue problem. The lights indicated a PCI Bus failure. After removing the expansion cards didn’t resolve the problem A DeLL tech installed a mobo twice. The second time all expansion cards were supposed to be replaced, but it doesn’t look like they were. It turned out to be a Hard Drive failure causing the problem. System would still boot but Hard Drive was causing the Press Del to Continue problem. DeLL sent a new Hard Drive. Installing new Hard Drive resolved this problem. The Puter seems to run very well. The mobo has an Intel 815E chipset, a DeLL invidia AGP 32mb Video Card, a DeLL SBLive Value PCI Sound Card, and a Conexant PCI Modem. After OE & chipset and some programs I installed a NetGear PCI NIC. All seem to be working fine. I did a clean install of Windows98SE ver. 4.10.2222. I installed the Intel® Chipset Software Installation Utility ver. 5.0.2.1003 08/27/2003 and the Intel® Application Accelerator ver. 2.3. There are two devices Windows can’t install. The first Windows calls a PCI System Management Bus. The other is Unknown Hardware. The mobo has no onboard sound or video. From other posts I see the Chipset Software from Dell resolves this problem. I tried directing Windows to the DeLL Resource CD to no avail. I have since returned the Puter and understand the LPT Printer and USB Scanner work fine. Friends say the Puter never ran better. I ran the Puter for 24 hours straight installing Programs without a burp except for of course AOL 9.0 Optimized. In the device Manager under Hard Disk Controllers, there is an ATA Controller listed but no PCI bus controller. I don’t know if this is typical or not.

My Questions. Can I install the Intel 800 Series Integrated Chipset, Driver v. 2.30.021, A04 from DeLL over the Intel® Chipset Software Installation Utility ver. 5.0.2.1003 08/27/2003 from Intel? Or Can I direct Windows to an inf file somewhere to install the software. I’ve unpacked the Dell chipset software, but don’t see an inf. file to direct windows to. I figure after the PCI System Management Bus software is installed the other device won’t be unknown anymore??? Would clearing the NVRAM resolve this. Are there jumpers the DeLL tech hasn’t set properly? Could this be related to the original Press Del toContinue problem even tho replacing the Hard drive fixed it, the lights did indicate a PCI Bus failure?