I've just started on PSP WUs again and the first one I returned has a new wingman, and I'm guessing it will take the Intel(R) Atom(TM) CPU N270 @ 1.60GHz a little while to complete it :)
I once ran a PPS LLR on an Atom-powered netbook just to see how long it would take. It took quite a while. My guess is that the Atom's architecture is particularly slow at floating point calculations and it will take much longer than the 1.6 GHz clock speed might suggest.
Searching through the database, I found a few tasks completed by an N570.
SGS takes about 50K seconds.
PPS-LLR takes about 25K or 70K seconds, depending on whether the number being tested is PPS or PPSE.
That's roughly 5 times slower than my 32-bit AMD Sempron 3000+, and about 20 times slower than my Core2Quad Q6600. Based on that, it will probably take an N570 about 2500 hours to complete the PSP task. So, if it's left on and crunching 24/7, it will be done in July.
My lucky number is 75898524288+1 (I am NOT an administrator anymore, so please don't PM me with questions. I can't help.)