Intel: Copper is out, Optic Fibre is in (in your PC that is)

Intel's Com­po­nents Research Lab is work­ing on ways to replace cop­per wiring between moth­er­boards and chips inside com­put­ers with faster, more energy-efficient opti­cal fibre. It's not going to hap­pen tomor­row, but soon.

Intel's Com­po­nents Research Lab is work­ing on ways to replace cop­per wiring between moth­er­boards and chips inside com­put­ers with faster, more energy-efficient opti­cal fibre. It's not going to hap­pen tomor­row, but soon.

The lab has cre­ated a pro­to­type sys­tem with chips con­nected to each other through eight opti­cal chan­nels trans­fer­ring data at more than 1 giga­bit of data per sec­ond for an aggre­gate band­width of over 8gbps (giga­bits per sec­ond). The indi­vid­ual chan­nels, called wave­guides, can trans­fer data at up to 3gbps.

That's slower than con­ven­tional opti­cal tech­nol­ogy — and even some stan­dard con­nec­tions in PCs today — but the entire unit is housed inside a chip pack­age and should be cheaper than cur­rent opti­cal parts. And even­tu­ally it will speed up.

The effort is largely aimed at dodg­ing some of the prob­lems loom­ing with metal inter­con­nects and buses. Chan­nels in PCI Express — a faster con­nec­tion for shut­tling data within a PC — can pass data at 2.5gbps, but metal chan­nels will likely top out at 10gbps and 20gbps because of sig­nal atten­u­a­tion and other problems.

Opti­cal chip com­pany Pri­mar­ion is work­ing on sim­i­lar tech­nol­ogy. Both Intel and Pri­mar­ion started exam­in­ing opti­cal inter­con­nects a few years ago.

Fibre is cur­rently being used to con­nect servers, but it will likely begin to con­nect boards inside com­put­ers in two to seven years. Chip-to-chip opti­cal con­nec­tions will start to appear in about seven years.

Intel is try­ing to remove some of the inher­ent dif­fi­cul­ties of opti­cal tech­nol­ogy by mak­ing as many of the com­po­nents as pos­si­ble on stan­dard sil­i­con wafers. The com­pany recently showed off a sil­i­con mod­u­la­tor that chops up laser light into 1s and 0s.

Not all com­po­nents can go into sil­i­con, though. Light can't be gen­er­ated out of sil­i­con, for instance. In addi­tion, the chip-to-chip inter­con­nec­tion con­tains com­po­nents that are made with gal­lium arsenide and ger­ma­nium, which raises man­u­fac­tur­ing costs. Still, enough of the tech­nol­ogy can be inte­grated into stan­dard sil­i­con chips to make the propo­si­tion viable

A quick look at stuff at The Micro­proces­sor Report sug­gests that opti­cal could cer­tainly advance over­all com­put­ing per­for­mance, but it won't be easy. Micro­proces­sors gen­er­ate sub­stan­tial amounts of heat, and opti­cal equip­ment can mal­func­tion if heated.