I still work on a lot of Compaq Proliant 1600s. In their day, they were a very versatile server, packing lots of drive bays and open expansion slots into a 5U package. They were also very reliable.

Now that they are five years old or even older, they are less so. But I've collected some good suggestions from Compaq and HP technicians about working on them.

The biggest problem with the 1600 is that so many parts are socketed. Over time, socketed components tend to work themselves loose. So, when a 1600 crashes a lot but will pass its built-in diagnostics with flying colors, the best thing to do is to completely disassemble it and put it back together.

If it seems to be having memory problems, don't just reseat the processor board and/or replace the memory. I had one 1600 exhibit memory failures that would not go away until I replaced the PCI board, of all things. Why? Beats me. The HP technician was as stumped as I was. So reseat that board too.

It never hurts to clean the connectors when you have the system apart. Get some zero-residue contact cleaner from a hardware or auto parts store. Be sure it's zero-residue. A lot of contact cleaners contain oil, which isn't going to help intermittent electrical connections at all. If in doubt, skip the contact cleaner entirely and clean the contacts with a cotton swab and rubbing alcohol instead. Need I also mention you need to stay grounded at all times while doing these procedures?

When replacing the PCI and CPU modules, you have to use a lot of force. Don't rely on the plastic releases on the back to put them in. Whenever I've seen a veteran Compaq technician reinstall one of these modules, he's slammed the module into the back computer with so much force that it moved the system. If you don't think you're going to break it, you probably aren't doing it hard enough.

Newer Proliant servers have many fewer socketed components, so their long-term reliability prospects are higher. They also usually have LEDs that indicate failed components, making diagnostics virtually irrelevant and system repair much more straightforward. But when replacement isn't an option just yet, it's nice to know there are things to do to return a 1600 to life.