I recently upgraded the CPU in one of my hosts. On my hosts page, the CPU for the "old" stats isn't properly showing the old CPU type, it's showing the new CPU. There's a second entry with the new CPU info. Any idea how to correct?

Are you sure that the "old" host (the one with your credits) shows the NEW CPU? The expected behavior would be for you to have a new entry in the host list with the new system configuration, and the old entry with the credits to reflect your old configuration. CPU is one of the attributes that BOINC uses to identify a unique/separate host; you won't be able to merge hosts with different CPU types, unless they happen to present the same CPUID to BOINC. This is the case with some older processors (such as PowerPC G3/G4) but I'll bet your "upgrade" probably involved a new processor from this decade.

I have 16 "hosts" that change CPU (and RAM, mainboard, graphics card, basically everything) all the time, and it's a complete gamble whether it gets a new CPID or not. It's about 50/50 I think.

After a XML export from the project and a host update on BOINCstats (only once a day!) BOINCstats also shows the correct CPU.

Here's my information. #1 has the incorrect info.

1 Intel(R) Core(tm)2 Quad CPU Q6700 @ 2.66GHz 1(4) Microsoft Windows Vista 348,608 87 2,350 12,225 334 -
2 Intel(R) Celeron(R) M processor 1.40GHz 1 Microsoft Windows XP 55,653 118 687 1,252 62 -
3 Intel(R) Core(tm)2 Quad CPU Q6700 @ 2.66GHz 1(4) Microsoft Windows Vista 1,460 1,167 1,460 1,460 136 253

Have you tried merging them? Unfortunately, you'll need to do that at all of the individual projects where that host has credit. However, if some things don't match up you may not be able to merge them.