The Nokia Ni500 is an external ADSL Modem/Router. It is a rather bad one. If at all possible, try to stay away from these. They are prone to terrible connections, due apparently to heat problems. Sometimes (at least once) known as a "Pie Warmer". Whatever the reason, they are a rather bad ADSL router that doesn't even support pinholing of ports.
If you are stuck with one:
You can try to avoid heat problems by taking the case off to give it more ventilation. When I did this I found the entire thing felt hotter than an overclocked Athlon. Maybe mounting a few fans around the board would help.
It seems that there is a EMF sheild over the chips to meet EMI regulations, however this acts as a heat reflector making the chips cool less efficiently. I suggest removing the large alloy sheild, mounting heatsinks on all the hot chips (using some sort of thermal epoxy) and a suitable fan to promote air flow. -- JamesSpooner
One page links to Ni500:
