oem cpu has no warranty at all,
if you burn it,
do you think the seller will generously give you a new replacement?
they will use any excuse to deny it.
and oem cpu is not supposed to be sold to individual, should be sold to system integrator only.
the price difference of retail and oem cpu is so small now, it's not wise to buy oem cpu.
even you're going to buy a killer aftermarket HSF for better temperature or overclocking,
you should still get retail cpu. If you damage the retail cpu during installation or burn it, amd or intel will generously give you a new replacement.
we should not call all oem stuff oem, some should be called bare.
for example, harddisk, bare drive being sold in local or online has same warranty as retail harddisk, only the oem one - in a brand name computer - doesn't have warranty from manufacturer to end-user. so you can see the difference of oem and bare from this example.
for vga card, real ATI oem card and the old day Diamond oem card have same warranty as retail, they shouldn't be called oem, bare is a better word. there are some ATI oem cards made by 3rd party now, these oem cards don't have warranty from ATI.
oem stuff is not always cheaper than retail,
harddisk is a good example,
when staples or dell is having promotion,
you can get retail maxtor hd even cheaper than the oem one.