Custom PC - UK (2020-08)

to see. Mechanical disk drives are in decline
in consumer PCs, as more and more of
our storage is replaced by tiny M.2 SSDs.
Meanwhile, an ever greater proportion of our
computing is dedicated to streaming video
services, online backups and even streaming
gaming services (although, we’re still very
sceptical of just how many PC gamers will
make that switch). Our PCs now have the
potential to become ever smaller and more
akin to terminals than all-in-one machines.

Most obviously,thishasopenedupthe
possibility forthevastmajorityofPCusers
to move to morecompactformfactors
such as mini-ITX.Withsuchboardsableto
accommodatetwoM.2SSDs,andsaiddrives
being readilyavailablein2TBcapacities
for now sensibleprices,it’seasytohave
all the storagemostofuswillneednotjust
in a tiny PC, butessentiallyintegratedinto
the motherboard.
The otherbigtrendthathasledtothis
shrinking of internalPCcomponentsis the
ever-growingcapabilityofUSB.Withtransfer
speeds nowhighenoughthatyoucanwork
directly froma USBdrive,andthelatest
standards supportingvideo,moreof
equipment canbeexternalised,forb
or worse. Whetherit’saudiointerfa
storage or evenexternalgraphicsc
much of whatusedtobeinsideour
is now sprawledall
march lookssettoco
latest 3.2 standardal
transfer speedsand
when it arrives.
But gettingbackto
the biggest, latestch
is the introductionof
increased thetotalba
from eight gigatrans
sec) per lane(126G
16 lanes) to 16GT/sec
per lane (252GT/sec
for 16 lanes).We’ve
already seenthis
greater throughput

in early PCI-E 4 SSDs, which have pushed

past the ~3,500MB/sec maximum speeds

of PCI-E 3 drives and towards ~5,000MB/

sec. Admittedly, most people won’t notice

that speed difference in day to day use, but

at least it’s there.

Indeed, the advantage of PCI-E 4 is set

to be minimal for the foreseeable future,

outside of niche applications. Graphics cards

don’t need it (especially given the dwindling

support for multiple graphics cards) and even

everfasterUSBandEthernetstandards

don’tparticularlybenefitfromit, evenif a

singlePCI-E4 lanecanprovidea 10Gigabit

Ethernetconnection.

Meanwhile,CPUsocketsregularlychange

astherequirementstosupportnewer

standardsforPCI-Eandmemorycomeinto

play,andofcoursewe’reallfamiliarwith

Intel’sregulartweakingofitssocketsto

‘simplify’itsCPUandmotherboardofferings.

Butbeyondthesetweaks,thereareno

realisticmajorchangesonthehorizonfor

mainstreamCPUs:wewon’tbereturningto

thedaysofslot-basedCPUsanytimesoon.

Whatwehaveseenis theintroductionof

fairlyextremesocketsintheHEDTandserver

larlywiththeintroductionof

tsfromAMD.

s

As for memory, there has been talk of

a major overhaul to how system memory

interfaces with CPUs, with a switch to a serial

form of communication being proposed. In

particular, by using through-silicon via (TSV)

technology (as used on the HBM memory

with AMD’s Fiji GPUs) where the memory is

built right on top of the CPU die, it would then

use an internal multi-lane serial link akin to

PCI-E to communicate with the CPU.

At least, that’s what some people predict

mighthappen.Inreality,though,there

areseveralreasonssuchanapproachis

unlikelytobetakenformainstreamPCs

anytimesoon.

Fora start,morelayersona CPUdiemakes

formoreopportunitiesforit tofail,making

chipsfarmoreexpensive.Thebenefitsare

uncleartoo.GPUsbenefitfromgettingas

muchmemorybandwidthaspossible,which

is whyAMDexperimentedwithHBM,butfor

CPUsit isn’tthelimitingfactorinthemajority

ofmainstreamcases.

Clockspeedis insteadfarmoreimportant,

andaddingmorelayerstoa CPUdiewould

onlymakehittinghighclockspeedsharder,

whilealsomakingit morechallengingtokeep

thechipcool.

Asfortherawcommunicationconduititself

• electricityandcopper– we’velongbeen
  flirtingwiththelimitationsofthisohsoslow
  mediumandexperimentshavebeengoing
  onforyearswithusingopticaltransmission.
  However,whileopticaldigitalcablingis
  wellestablished,andofferssignificant
  advantagesinbandwidth,rangeanddamage
  resistance(itdoesn’tcorrodeorgetaffected
  byelectromagneticradiation),we’ve yetto
  seeit usedforPCBtracesorona microscopic
  ourprocessors.
  des
  ntinuetoo,
  o fo 2
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ThreadripperCPUsis

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Silicon Photonics allows for the laser beams

used in optical cabling to be generated

on-chip, but we’re still a long way from

optical processors or motherboard traces

7+($'9$17$*(2)3&,ˎ(,6

SET TO BE MINIMAL FOR THE

FORESEEABLE FUTURE