The SMP loss of which I write is the points you'd get running the SMP core. If you could get 1 CPU core to handle feeding both GPU2 clients, you might be able to run the SMP core. Apparently you'd have to be running Vista for that to succeed and add to your output, though.
I wonder why you're not getting more output from your 8800GT 256 cards, though. I'm getting ~4700 PPD from my one, and it's fed by a 2.0 GHz A64-3200. I mean to test what happens if I run the console client with it, which I'm betting will be a loss of output, but I've got other things ahead of that for now.
I think I read something about the v. 1.07 core and its disappearance or existence on the foldingforum.org site, but am not sure where. The gist was that, vague memory problem here, but there was something about the 1.07 not being updated in version number at least at first, and I thought Pande said that was going to be fixed. It may well have already been fixed before I ever downloaded the GPU2 client last week, though, since the thing had been out by some time in June.
I found
this thread which says some stuff about it, but was closed by
7im, but he calls the thread a duplicate and implicitly points to a thread linked in it, which is
this one, which scolds saying v. 1.07 isn't available now and whatever. Some others said the installer was updated in the first linked thread, though, but maybe you have to remember to delete files from \Documents and Settings\
username\Application Data\Folding@Home-gpu area or something.
I'm more confused about things the more I read, because people espouse ideas and moderators or others don't always correct them, and then there are contradictions in other threads. Pretty much as you said.
In the end, were I in your situation I'd uninstall the client, then search for FahCore_11.exe and if any is found at minimum rename the file(s), and then download another copy of the installer and re-install from it, and see if it then begins reading the required environment variables (which in XP can be set in System Properties->Advanced), as mentioned in this (currently 6 page long) thread,
A new Nvidia core (v1.07) for users w/ multi-gpu boards.
Flying Fox: The cores are launched by the executable I mentioned. Changing that thing's assigned CPU core is the only plausible way to do it. One could assumedly find or if need be write a utility to sleep and every minute or so wake up to make sure all cores are where they ought to be, but we'll cross that bridge when we come to it if the environment variables are officially not working.
Someone in a thread here in the last day or so said something about a program he found to assign affinity, but I'm out of steam now so others can find it.