You have to bear in mind that not every partner gets the same price and the more chipsets you buy, you'll get a better price.
A motherboard partner has to pay an average of $25 for the Nforce 4 Ultra chipset. If we are talking about Nforce 4 standard chipset you should be able to get it for less than $20 while the Nforce 4 SLI is an expensive part. You have to pay between $40 and $45 for Nforce 4 SLI and that is still cheaper than Intel wants for its top line chipsets.
Intel's flagship 955X chipset costs exactly $50 while you can buy an Intel 945G chipset with integrated graphics for $40. Intel's 945P will cost $35 while you need to pay $5 less for anon IGP chipset.
The cheapest Intel chipset is 848P and it costs $21. The cheapest IGP is the Intel 865GV and should cost motherboard manufacturer $24.
When it comes to mobile chipsets you need to pay $39 for Intel 915 GMS while the cheapest "Centrino" chipset is Intel 852GM should cost you $27. µ