When I worked at Dell they used direct negotiation to deal with things like this (the major chips PCs). The ODM who makes the machine buys specific lots of chips and pays one (high) price X and passes that onto the OEM. The OEM pays it, but also negotiates a rebate which the chip maker pays directly to them. The rebate involves lots of negotiation it depends on lots of things; volume, co-branding, use of competing parts and all sorts of other things. It's very hard to know what price a large OEM pays for each processor.