Here's some more interesting information from Eike Belgardt who's in Germany:
Thank you for your great page about the Acernote Light 350PC. It was of extreme help to bring my own 350PC back to life.
I have pulled one of these notebooks out of the garbage at the company I'm working for. The
harddisk was broken, it had no memory upgrade (only the factory-installed 8 MB) and the touchpad did not function. I've replaced the touchpad with one from a broken 350 (486 based), replaced the harddisk with an IBM Travelstar DARA-206000 (6 GB, which is recognized by BIOS version r0-h1 without problems) and maximized the memory to 40 MB.
But now to the most interesting upgrade: I've replaced the originally installed Pentium 100 with a AMD K6 clocked with 166 MHz ! The upgrade
is easy: Just add a hole for the missing mechanical pin at location AH32 of socket 7 (I've used a hot needle for this procedure). The bios will recognize the K6 as Intel Pentium processor. The mainboard is able to provide the 2,9 V needed for the K6 by setting SWY1 to both off. With SW2 set to ON-ON-OFF-OFF you will get 166 MHz. My system did not boot at 200 MHz, so I'm currently underclocking a 200 MHz K6 cpu at 166 MHz. This combination seems to run rock stable (with the precondition of using the software-"cooler" Rain 2.0 under Windows 98).
The main advantage of using the AMD K6 is the big first level cache (64 kB) compared to a Intel Pentium (16 kB) or Pentium MMX (32 kB), which is
important due to the fact that the 350PC has got no second level cache. And the K6 also supports MMX. By using the free tool setk6 (provided by the German c't computer magazine) you can enable K6's write allocation which gives an additional performance boost in memory access.
With K6@166 MHz and enabled write allocation CPUMark 99 gives me a score of 6.99 under Windows 98SE.
My future plan is to modify the voltage regulator for 2.2 V. Then you can even use an (maybe
underclocked) AMD K6-III, which will add a second level cache to the 350PC ! I will inform you if I'm getting this to work :-) .
Thank you again for this great website about 350PC !
Bye, Eike Belgardt
I must admit that it's - despite my first message - unfortunately not possible to clock the K6 with 166 MHz for a long time. It simply get's
too hot as I had to notice yesterday. But at 133 MHz it seems to run stable and cool enough for continuous operation. I've also tried a 233 MHz Pentium MMX and have made the same experience as you. After barely 30 minutes the computer reboots because of heat problems.
The CPUMark 99 score of the K6@133 MHz is 6.69 which is still a good result compared to the 233 MHz Intel Pentium MMX.