You can always look for some value sticks (eg Kingston Value 400 MHz CL3) built with Infineon / Qimonda CE-5/CE-6/DE-5 or Aeneon C/D-die. They are usually very cheap and should do 200 MHz (DDR 400) 2-3-2 easily even on NForce 2 (and >230 MHz 2-3-2 on K8/s478).
Example ICS-es:
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Another choice would be a 1 GB Elixir/Nanya CS-5T produced in 2009-2010, maybe later too. They are >230 MHz 2-3-2 capable on K8/s478. But Nanya produced a lot of different chips and you might easily get something significantly worse by mistake (eg there are old CS-5T 256 Mbit from 2006/7, which max out at around 240 - 250 MHz 3-4-4), so I would rather pick Infineons.
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P4 3.0C, P4C800-E Deluxe, 1 GB RAM, X800PRO 128 MB AGP, SB Audigy, Chieftec 400 W, XP SP2
XP2000+, KT2 Combo, 512 MB RAM, GF2Ti 64 MB AGP, FM801, FSP 400 W, 98SE
C400, Garry, 128 MB RAM, Voodoo 2 12 MB, Virge 4 MB, ALS100 Plus+, Compaq 200 W, 98SE