You should try 'cpuburn' (burnk7 for AMD)
http://users.ev1.net/~redelm/
It gets my system 4-5 degrees hotter than anything and is really taxing on the +3.3V and/or +5V on most PSU's, my AOpen 300W (my 8K7A only uses the +5Volt line) goes from 5.20 to 5.01-5.02 with burnk7 while prime95 or whatever only lowers it to 5.10 Volts.
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Pump:Eheim 1048,
Radiator:LPD radiator 100x150x20mm,
CPU block:DD Maze-2,
GPU block: DD GPU block,
Chipset block:Zalman NB32
AMD XP 1500+, EpoX 8K7A, PoV GF3Ti200
Pic of my YY-cube