Should You Use Fewer Larger HDDs or More Smaller HDDs?
The technology behind hard drives has evolved RAPIDLY! In just the last few years we have seen HDDs hit over 20 terabytes, seen the number of platters being squeezed into a single hard drive casing reach more than 10 and the performance and durability of these drives somehow continue to improve too! Still, one area that we have seen very little change in over the years is the price per terabyte of most HDDs. Despite the range of capacities available from most HDD brands (Seagate, WD, Toshiba, etc), the cost of the latest and largest HDDs still maintains a hefty price tag, whilst the smaller capacity drives (still broadly keeping their lower price point) are more readily available, occasionally on offer and this leads alot of data storage buyers to ask themselves – Is it better to buy a small number of MASSIVE hard drives or a larger number of SMALLER HDDs? Thanks to modern development and efficient evolution of RAID (redundant array of independent disk) management in NAS and DAS systems*, alongside storage enclosures now ranging from as little as 2 Bay desktop case scale all the way upto 24-60 Bay rackmounts, it is actually quite easy to achieve the same amount of capacity of a handful of ‘max capacity’ drives with a smaller cluster of more affordable smaller drives. So, today I want to look into the benefits/downfalls of either setup and hopefully help you decide whether you need to opt for bigger or smaller hard drives in your data storage setup in 2023 onwards.
Note – If you are looking for the Best Price per Terabyte of any Hard Drive from WD or Seagate, you can use our HDD comparison tool that will provide you with the best hard drive for your needs if you want to use X number of drives, have at least X amount of storage, using X type of RAID and/or spend X amount of money. Find out more about the tool and how to use it HERE – https://nascompares.com/2022/12/28/how-to-choose-the-best-value-hard-drive-and-best-price-per-tb-get-it-right-first-time
*NAS = Network Attached Storage, always featuring RAID management onboard. DAS = Direct Attached Storage, with them either having on-board/hardware-RAID or will be JBOD (Just a Bunch of Drives) that needs your host computer to set up and maintain the RAID
Why Should You Use A Larger Quantity of Smaller Capacity Hard Drives
So, first up, lets discuss the advantages of opting for a larger number of smaller capacity hard drives in a RAID in your NAS/DAS system. It is worth remembering that when I am discussing smaller capacity HDDs, that (in order to keep things simple to differentiate) I am classing any HDD 1-10TB as ‘smaller’ capacity and 12-22TB (with 24TB and 26TB arriving quite soon) as ‘large’ capacity. So, lets discuss why you might want to go high volume, low capacity!
More HDDs Can Cost less than fewer larger HDDs in the right RAID Configuration
A massively overlooked advantage when it comes to choosing a larger number of smaller capacity HDDs is that, thanks to the development of RAID technology, you can often save a good 10-15% of the cost of your data storage media by choosing a RAID 5 configuration of smaller HDDs, rather than a RAID 1 with smaller drives. Larger HDDs (which already cost significantly more, but are similar in price per TB broadly) provide you with a HUGE amount of storage space. However, because of the importance of your data (home or business), you are going to need to factor in things like backups and redundancy*. If you are buying at least 1x MASSIVE 20TB or 22TB hard drive, then you have to accept that you are going to buy AT LEAST 1 more (to act as a backup or for redundancy in a RAID 1). Below is a breakdown of the pricing of WD Red Pro and Seagate Ironwolf Regular NAS Hard Drives (enterprise/pro drives have a higher build standard, faster, longer warranty and ultimate around £30-50 more than their non-pro alternatives):
|Cost of NAS Hard Drives in Jan 2023 (5/1/23)|
|Seagate Ironwolf HDDs (Regular)||WD Red Pro HDDs (Pro Series)|
|1TB – $35
2TB – $65
4TB – $105
6TB – $158
8TB – $177
10TB – $224
12TB – $258
14TB – $271
16TB – $309
18TB – $389
|4TB – $140
6TB – $173
8TB – $215
10TB – $245
12TB – $253
14TB – $270
16TB – $298
18TB – $349
20TB – $419
22TB – $551
In most cases, the price per terabyte on both sides will remain largely consistent at each capacity. HOWEVER, when you start putting these drives into a NAS/DAS enclosure and acting in the RAID configuration, it soon becomes apparent that the ben efits in Drive #s in a RAID 1 vs a RAID 5 immediately show a saving in almost every single capacity the smaller you go! Below are two examples of achieving 12TB in a NAS enclosure using RAID 1 vs using RAID 5 (so, still maintaining 1 disk drive failure protection and having 12TB of storage to use):
|12TB Storage in a RAID 1 MIRROR||12TB Storage in a RAID 5|
So, often, it can work out cheaper to purchase multiple smaller hard drives rather than fewer larger HDDs in order to hit certain capacity levels, whilst still maintaining an identical level of redundancy. This does mean you will need to choose a NAS of a larger bay number/size, ut more on that later.
*Backups and redundancy should not be confused as the same thing! Backups are a complete copy of the same data in a different location (physically, ideally). Redundancy can be thought of as a safety net. In a RAID (in most cases) you will have to supply enough media/space to facilitate the system keep your data intact in the event of a mechanical drive failure. Redundancy is NOT a backup, because it is in the same physical computer location and intertwined with the primary storage – so lose/break the NAS/DAS and redundancy is useless!
Bigger HDDs Can result in ‘all eggs in one basket’ issue
Possibly one of the early benefits of RAID (aside from benefits in larger storage in general) was to ensure that your storage had that safety net in place to withstand a drive failure. HDDs are like any other kind of mechanical technology and as soon as you introduce moving parts, pressure, workloads over years and electricity to run, you are immediately going to have to accept that they are open to one day breaking down. However, larger capacity HDDs (in particular larger capacity drives used in smaller RAID/deployment configurations) introduce the ‘all eggs in one basket’ principle. If you have a HUGE amount of data in one single container, that means that just that 1 container has to fail to lose EVERYTHING! There are arguments for and against having this single-layer failure point vs the statistics of a multi-point of failure setup (will touch on that later), but bigger hard drives and the immediate necessity to double that capacity in RAID/Backups can be daunting enough for some more cost aware users to cut corners in their data storage setup (perhaps being a bit casual in their data storage retention and depth policies). Opting for multiple drives in smaller capacities means that although you have multiple drives instead of one, that your data is a little more spread out. There IS a counterargument to this but I will touch on that later.
Smaller Capacity HDDs are more regularly on SALE
This one is a little more obvious than the differences in RAIDD configs and capacity we have already covered. Smaller capacity HDDs have a higher chance to be on offer at retailers than larger capacity drives (by quite a noticeable margin!). This is down to three main reasons:
- Smaller capacity HDDs have been available for a longer amount of time in the market and can therefore extend to more creative pricing
- Smaller capacity HDDs, because of their longer amount of time since release, have larger stock available post-manufacture and that means the buy/sell demand is a little more favourable to the buyer
- Smaller capacity HDDs often require less hardware resources in their production than larger capacity HDDs with their more enterprise/pro design in line with improved R&D
Ultimately, this means that smaller-capacity HDDs are more regularly on offer than their larger-capacity alternatives. In particular, 4TB, 6TB and 8TB HDDs are often found on promotion at the majority of retailers and when you fact that in with the benefits of RAID 5 vs RAID 1 in your configuration, this can all add up to real savings. Here are a few examples from very recently:Click to view slideshow.
Larger capacity HDDs are occasionally on offer, however, these are far, far less frequent and rarely see the price drops found in the smaller capacities (outside of big, BIG sales such as Black Friday)
More HDDs in a RAID (almost) Always results in Higher Performance
Another big, big benefit of using multiple smaller HDDs in a larger RAID config compared with larger HDDs in a smaller RAID is to do with performance. Depending on the number of drives in the RAID, you can see some fantastic improvements in performance. Years ago, RAID configurations such as RAID 5 and RAID 6 were seen to have a performance penalty because of the extra work being done by the CPU/Resources of the NAS keeping them running smoothly and safely. However, in recent years thanks to the improvements in NAS CPUs being used and the software that is running on them, RAID 5/6 doesn’t have anywhere near the performance loss it once did. In fact, RAID 5 and RAID 6 can grant you some great benefits. This is thanks to a RAID allowing read and write activity being spread across multiple disks at once (as opposed to a single drive being accessed in a normal 1 drive setup). Different RAID configurations result in different benefits (with a RAID 0 being the fastest, but utterly lacking any kind of redundancy/safety-net):
So, for example, using Seagate Ironwolf HDDs at the prices above, if we were to compare 2x 16TB HDDs in a RAID 1 ($618) vs 3x 8TB HDDs in a RAID 5 ($541) vs 5x 4TB HDDs in a RAID 5 ($525), the result is that although all three RAID configurations will provide 16TB of available capacity and protection, the LOWEST PRICED 5x4TB RAID 5 Setup will actually give the HIGHEST PERFORMANCE as it is the most drives being read/written with at any given time.
Bigger Capacities are more often ‘PRO’ or ‘Enterprise’ ONLY
This is something of a growing trend, but because of the development of larger HDD capacities requiring modern storage technology to improve in big ways (to increase that storage cap, but also remain stable and maintain performance), we are starting to see more and more HDD brand release big, BIG capacities, but limit them to ONLY the PRO or Enterprise tiers of their portfolios. Seagate doesn’t do this too much on their NAS series, but WD Red has been involved in this kind of range division for a few years now, with their WD Red Plus series capping at 14TB, but their WD Red Pro range now available in upto 22TB (with 24TB around the corner). See below from the official WD HDD site:
So, if you DO want larger capacity HDDs, do not be surprised if it means you are forced to opt for more industrious HDDs in Pro or Enterprise ranges. This does mean longer warranties and slightly higher individual performance, but also means higher power use and one other big issue that main smaller/home/SMB NAS/DAS users complain about when in closer proximity to larger HDD arrays. Namely noise…
Enterprise and PRO HDDs make more click-and-access noise
Yep, Noise. It shouldn’t come as a big surprise, but when you cram as much hardware into a single 3.5″ HDD casing, then those moving/mechanical parts are going to have to work harder! In the case of larger HDDs that are forced into the Pro/Enterprise ranges due to their hardware development, the result is that these drives make noticeably more noise when they are spinning up, being accessed and especially during high-volume access. This is because larger capacity HDDs have more platters (the circles inside that your data lives on) and the actuator/arm (the bit that is constantly moving across the platters to read/write data all over those disks) is constantly having to move in/out/up/down. This is particularly noticeable with even a single larger capacity HDD and when you have multiple running in a single RAID, the noise is especially noticeable (often louder than the NAS that they are inside!). Here is the noise of 4x WD Red Pro 20TB HDDs in a 4-Bay Synology DS920 NAS during high access:
Now, this is not going to be a problem for everyone. If you plan on running your NAS far away or in a part of your home/office that is suitably noise cancelled, then the noise of larger HDDs is not really going to be a factor for you. However, those of you who are going to be in close proximity to your NAS, you will definitely notice the industrial quality of larger capacity HDDs!
|WD Red Pro Noise||WD Red Plus Noise|
Why You Should Use a Smaller Quantity of Larger Hard Drives
There are two sides to every coin! As good as the points above are that highlight the benefits of smaller HDDs in larger quantities – there are also a whole bunch of advantages to opting for larger HDDs instead. Let’s go through them now.
Using Bigger Capacity HDDs Can Mean You Can Use a Smaller/Cheaper NAS
Yep, despite my highlighting that the using multiple smaller HDDs in the right RAID can result in a lower price per TB (after redundancy) vs larger HDDs – using MORE hard drives will mean that you need to use a larger NAS/DAS system. Larger NAS/DAS systems are always more expensive, as they need to have more physical space, resource use in production and power/PSU sizes to run the larger enclosure. Add to this, thanks to memory shortages right now, that smaller scale NAS systems are starting to arrive with more memory by default (as 2-4GB is becoming less cost-effective to produce with chip shortages) and often with little/no increase in the base price. For example, below is the TS-264 and TS-464 NAS. Same CPU, design and ports – however the 2-Bay system has 8GB memory by default AND IS STILL $134 cheaper!
So, this can often mean that you can save money on smaller quantities of larger capacity HDDs becuase the enclosure they are going in is cheaper over all.
Using More HDDs in a RAID Means Increase Points of Failure
Yes, this might seem a little counterintuitive, given my comments earlier about single containers vs multiple and failure. However, using more HDDs in a single RAID array opens the door to more points of failure (i.e more drives, more chance of a drive failure). Now, on the face of it, this kinda balances against big drives anyway, but there are some users who want to have as fewer points of failure in their system as possible, as then they have fewer areas to monitor. This is further exacerbated when you factor in things like an unexpected power failure during heavy write operations breaking multiple drives at once and/or potential bad-batches at the factor level. Ultimately more/less HDDs is going to be something of a percentages game and although I personally do not really subscribe to this as a reason to avoid smaller HDDs in larger quantities, I know there are some users who would disagree!
More HDDs mean increased Power use/Electricity cost
This is a smaller factor, but one that (in these very energy cost aware and climate-concerned times) is growing in importance for many users. Most HDDs (big or small) use a nearly identical amount of power and you cannot really see the running power use difference between, eg. a 2TB and 20TB HDD, unless you have multiple drives running at once. However, if it DOES add up and its is further compounded by the increased power use of larger NAS/DAS systems that have more bays. Larger RAID configurations will also increase CPU usage a pinch too and once you add all these factors in 24×7 systems like those of NAS rackmounts and large-scale desktop tower systems. Below is how the power use of the WD Red Pro series compares across all the capacities:
Not much between them! Using fewer HDDs (i.e larger capacities) in a smaller NAS/DAS enclosure with an easier-to-manage RAID configuration will always result in a smaller power consumption overall (whether you are concerned with energy use environmentally or the electric bill at the end of the month – though for the latter, you will need to factor in the cost of the larger drives, remember!). Of course, we are talking about very small margins here, but for those running on limited or low power capacity situations/environments, these small differences can have BIG impacts!
More HDDs mean an increase in drive noise in drive spin-and-vibration
NOISE! It’s back again, as although the larger HDDs make more noise in clicks, access and spin noise in the larger capacity HDDs, it is also worth keeping in mind that if you decide to go for a larger collection of smaller capacity HDDs that you will encounter a different kind of noise issue sometimes. Namely, vibration (a persistent humm) noise in the larger NAS/DAS systems with more drives inside. Although this is nowhere near as annoying as the clicks and whirs of the larger capacity drives (in my opinion at least), it CAN be very annoying for those working close to the NAS/DAS and are sensitive to persistent humming. Additionally, larger capacity NAS/DAS systems (in 6-Bays and above ) that you will need to support a larger RAID array of smaller capacity HDDs arrive in mostly metal NAS enclosures (2-4 Bay NAS are normally 60/40 plastic outside and aluminium inside). These metal chassis amplify that vibration hum too! Then there s the larger NAS enclosures needing improved cooling and ventilation systems to maintain cool operational noise over 24×7 use – at least 2 fans, with multiple smaller fans sometimes for the PSU and CPU respectively. It all adds up and are factors of noise that users considering larger RAID arrays of smaller HDDs should consider!
Larger Capacity HDDs Benefit from modern build techniques and development
This is certainly something of a double-edged sword (and one that will come down to you, the end user, and how you feel about ‘new tech’ at launch) but when HDD manufacturers like WD and Seagate invest heavily in developing new techniques to improve the level of capacity, durability and performance in their drives – they almost always apply these new techniques to just the larger capacities! Most of the time, these will never be extended to the smaller capacities, as either the margins are too thin, the benefits are not needed on these established lines or they are looking to get as larger a return on investment (ROI) as possible by targeting new and exciting larger capacities that trend well. So, in the last two years we have seen exciting techniques being developed to increase storage capacity massively, such as Heat Assisted Magnetic Recording (HAMR), Energy Assisted Magnetic Recording (EAMR), OptiNAND for leveraging flash storage for drive I/O space adding to drives to free up traditional storage space and this will soon be moving forward into Microwave Assisted recording (which is what will be opening the doors all the way to 50TB and 100TB HDDs by the end of the decade). Then you have developments such as Mach 2 from Seagate that will allow twice the read/write activity of HDDs that make the jump from 250-270MB/s over SATA all the way upto 440-450MB/s. Practically all of these developments will be extended to the largest capacities and not suitable/available for the smaller ones. HDD technology develops FAST (see the video below that details the development of WD Red HDDs in the last 10 years for more of an idea how much has changed):
Of course, there are some users who will happily avoid the newest, largest and most expensive HDDs as they enter the market – instead wanting to see them out in the field for a whilst to ‘work out the kinks’ before they choose to invest their money. There are arguments on both sides.
More HDDs vs BIG HDDs – Conclusion & Verdict
There are plenty of reasons why you should opt for smaller or larger Hard drives that extend to alot more than ‘which one costs less’, with factors such as power consumption, performance, noise and durability being the main factors for business users and home users alike! On balance, larger-scale HDDs are always going to be designed, presented and released with business in mind. If you are a home user, you are much better off getting smaller-capacity HDDs, grabbing a few good bargains along the way, and get yourself a much more capable and usable NAS/DAS system to populate. Business users, who tend to produce the most data, use the HDDs for longer sustained periods and need assurances of the drive withstanding this larger usage are much more in position to take advantage of larger HDDs (longer warranties, more space, higher workload rates, etc). These are NOT iron rules and your own personal setup might well differ. To summarize though:
|Reasons to Buy Larger Quantities of Smaller HDDs||Reasons to Buy Larger HDDs in Smaller Quantities|
|Higher RAID Performance when you have more HDDs
Better Price per TB in the right RAID of smaller HDDs vs Big
More Regular Offers/Sales on Smaller Cap HDDs
Larger HDDs make more running noise individually
Larger HDDs are often Noisier in Access
More HDDs opens the door to 2 drive Failure Protection
Smaller Capacities have more proven success in operation than new larger drives
|Longer Default Warranties when drives are PRO/Ent only at high Cap (3yr vs 5yr)
Higher Individual Drive Performance
Access to Modern HDD R&D + Techniques
Lower Power Consumption in smaller #s and smaller NAS’
Smaller NAS/DAS systems = Lower NAS/DAS Cost to Buy
Fewer Points of Failure
Larger Bay NAS = More Vibration NAS Noise and Fan Noise
If you are thinking of buying New Hard Drives (and you found this guide helpful), please use the links below to take you to Amazon, as it will not cost you anything extra and will result in a small % in commission from ANYTHING you buy being sent through to us at NASCompares (just me and Eddie) which goes directly back into making more videos and articles. Thanks!
Alternatively, you can visit one of the retailers below, which will also help us make further content too! Thanks for being awesome!
LET ME KNOW ABOUT NEW POSTS
Enter your email address to subscribe to this blog and receive notifications of new posts by email.
Get an alert every time something gets added to this specific article!
This description contains links to Amazon. These links will take you to some of the products mentioned in today's content. As an Amazon Associate, I earn from qualifying purchases. Visit the NASCompares Deal Finder to find the best place to buy this device in your region, based on Service, Support and Reputation - Just Search for your NAS Drive in the Box Below
Need Advice on Data Storage from an Expert?We want to keep the free advice on NASCompares FREE for as long as we can. Since this service started back in Jan '18, We have helped hundreds of users every month solve their storage woes, but we can only continue to do this with your support. So please do choose to buy at Amazon US and Amazon UK on the articles when buying to provide advert revenue support or to donate/support the site below. Finally, for free advice about your setup, just leave a message in the comments below here at NASCompares.com and we will get back to you. Need Help? Where possible (and where appropriate) please provide as much information about your requirements, as then I can arrange the best answer and solution to your needs. Do not worry about your e-mail address being required, it will NOT be used in a mailing list and will NOT be used in any way other than to respond to your enquiry. [contact-form-7]
Support What We Do
Terms and Conditions Alternatively, why not ask me on the ASK NASCompares forum, by clicking the button below. This is a community hub that serves as a place that I can answer your question, chew the fat, share new release information and even get corrections posted. I will always get around to answering ALL queries, but as a one-man operation, I cannot promise speed! So by sharing your query in the ASK NASCompares section below, you can get a better range of solutions and suggestions, alongside my own.