32 APRIL2020|COMPUTER SHOPPER|ISSUE386
WDBlueSN550
★★★★★
£100•Fromwww.amazon.co.uk
Small files
Largefiles
Huge files
0% -50 Reference + 50 + 100
Seepage84forperformancedetails
CAPACITY1TB•COST PERGIGABYTE10p•INTERFACE
NVMe•CLAIMEDREAD2,400MB/s•CLAIMEDWRITE
1,950MB/s•WARRANTYFive yearsRTB•DETAILSwww.
westerndigital.com•PART CODEWDS100T2B0C
SPECIFICATIONS
417MB/s
1,161MB/s
1,086MB/s
INTERMSOFmakingimprovementson
previousgenerations,there’snotmuchthat
cantopthewayinwhichtheBlueSN500
(Shopper 377 )switchedWD’sentry-levelSSD
rangefromSATAtoNVMe.
Evenso,itsdirectsuccessor–theBlue
SN550–hasbeenpositivelyshoweredwith
upgrades.There’sanew1TBcapacityoption,
joiningthe250GBand500GBdrives,andits
TLCNANDmemoryis96layers;amore
modern,denseralternativeto theBlue
SN500’s64-layerNAND.
Althoughthemoveto 96-layermemoryis
moreaboutswellingcapacityandefficient
productionthanitisaboutenhancing
performance,theSN550promisesto be
faster,too.Alotfaster:themaximumread
speedisquotedat2,400MB/s,upfromthe
SN500’s1,700MB/s.The1TBmodel,whichis
whatwe’vegotherefortesting,alsoclaimsa
substantiallyquicker1,950MB/swritespeed
thanthe1,450MB/sof the500GBSN500.
VALUE PROPOSITION
Thebestpartisthatalltheseimprovements
haven’timpactedtheBlueseries’
characteristiccheapness.The1TBmodel
worksoutatapittanceof 10ppergigabyte–
aboutascheapasNVMedrivesof thissize
cancome,atleastfromabrandwithWD’s
clout.The500GBmodelisalsoavery
wallet-friendly13ppergigabyte, and
although the250GBistheworstvalueof
the threeat16.4pgigabyte, that’snormal
forsmallercapacities.Besides,the£41
outlayisstillrelativelysmall.
However,there’sstillaverygoodreasonto
spendonthelargercapacity:that1,950MB/s
writespeedisexclusiveto the1TBmodel.
Whileallthreevarietiesshareareadspeed,
writespeedisdownto 1,750MB/sonthe
500GBmodelandisjust950MB/sonthe
250GBmodel.Again,it’snotremotelyrare
forlower-capacitydrivesto beabitslower
thantheirbiggerbrothers,butlosingwell
VERDICT
The follow-up to oneofthe best budget SSDs gets even higher topspeeds, while keeping the price low
1TBSSD
over halfthemaximumwritespeedistough
to swallowatanyprice.
Ofcourse,thesearealljustWD’sown
figures,soit’stimeto seehowatleastthe
1TB SN550standsupto ourbenchmarks.
CrystalDiskMark’ssequentialtests,which
usuallyshowastoragedriveatitsnimblest,
givesolidbackingto theofficialfigures:in
fact,by recordinga2,408MB/sreadspeed
anda1,976MB/swritespeed,theSN550very
slightlyexceededitsquotedperformance.
Inthe4Krandomtest,however,itonly
manageda279MB/sreadspeedanda
190MB/swritespeed.Notonlyareboththose
resultslessthanhalfof whattheKingston
A2000(Shopper382)–anonlymodestly
moreexpensiveSSD–achieved,they’realso
alittlelowerthanthoseof thelast-gen
SN500.We’renotentirelysurewhy,thoughit
maybebecausethemoredenselypacked
96-layerNANDtakesabitlongerto sort
throughthan64-layer,evenifonlyinvery
specificconditions.
UP,UPANDAWAY
FortunatelyfortheSN550,itshowedsome
goodperformanceimprovementsinourown
filetransfertests,whicharedesignedto
reflectreal-lifeperformancemoreaccurately
thanthesyntheticCrystalDiskMark
benchmarks.Inthehugefiletest,for
instance,itaveragedareadspeedof
1,195MB/sandawritespeedof 1,127MB/s,
bothupontheSN500’srespective1063MB/s
and952MB/s,fornoextracost.
Itrepeatedthisfeatinthemore
demandinglargefilestest,ultimately
managinganaverage1,110MB/sreadspeed
andanaveragewritespeedof 1,061MB/s.
BudgetSSDsoftenfailto slippastthe
1,000MB/smarkinthisparticulartest–as
boththeSN500andthesimilarlycheap
CrucialP1(Shopper373)did–butthe
SN550 droppedonlyslightlybelowits
huge filetestresults.
Itwasonlyinthesmallfilestestwhere
the newerdrivefaltered,averagingadecent
butstilllessimpressive456MB/sreadspeed
anda377MB/swritespeed.Thelatterisonly
levelwiththeSN500’sshowinginthesame
test,anditsreadspeedisactuallylower:the
SN500averaged475MB/s.
Betweenthisandthe4Krandomtest,
we canconcludethattheSN550is–
bizarrely –muchfasterthantheSN500in
simpler,lesstaxingfiletransfersbutequal
to orslowerthantheoldermodelinthe
most difficultones.However,whenitcomes
downto achoicebetweenthetwo,westill
thinktheSN550isthebetterbuy.Mostof
the timeitwillbethefasterSSD,andby not
insignificantmargins.
FOND MEMORY
Also,consideringthisisabudgetSSD
designedforrelativelybasicPCs,it’sprobably
goingto facemainlysimpletasks.Werethisa
high-level,workstation-gradedrivesuchas
theSamsung970Pro,therewouldbemuch
greatercauseforconcern.
Assuch,it’sdefinitelyworthconsidering
theBlueSN550ifyou’rebuildingasimplePC
orwantingto upgradefromyourSATA
storageonthecheap.Werecommendgoing
forthefaster1TBor500GBmodels,butit’s
arecommendationallthesame.
JamesArcher
