Seagate Exos vs WD Ultrastar
Exos and Ultrastar are the two dominant enterprise HDD families for datacenter, homelab, and high-capacity server storage. Both are rated for 24/7 operation, carry 5-year warranties at retail, and are designed for multi-drive chassis with vibration tolerance. In practice the choice often comes down to price at the capacity you need, firmware compatibility with your HBA or backplane, and whether you prefer Seagate or WD support.
Quick comparison
Exos (Seagate) and Ultrastar (WD/HGST legacy) both target the same workloads: always-on servers, JBODs, and storage arrays. Exos X-series tops out at 24 TB with helium-sealed models; Ultrastar HC-series reaches similar capacities. Both offer SAS and SATA interfaces. Workload ratings are typically 550 TB/year, with 2.5M-hour MTBF. For most buyers, the lowest price per TB at your target capacity is the right pick.
Prices updated hourly from Amazon US and UK. All links go directly to the retailer. Details.
Seagate Exos — Current Prices
New Seagate Exos enterprise drives sorted by price per terabyte. Includes Exos X-series helium models across all available capacities.
Seagate Exos 7E8 HDD 512E/4KN SAS
Seagate Enterprise ST3000NM0025 3TB 7200RPM SAS 12.0 GB/s 128MB 512n Enterprise Hard Drive (3.5 inch, Exos 7E8 HDD 512N SAS)
Seagate Exos X24 24TB internal server Hard drive ST24000NM000C 3.5" HDD SATA3 512MB 7200RPM
Seagate 14TB HDD Exos X14 7200 RPM 512e/4Kn SATA 6Gb/s 256MB Cache 3.5-Inch Enterprise Hard Drive (ST14000NM0018)
Seagate Exos X14 ST12000NM0008 12 TB Hard Drive - 3.5" Internal - SATA (SATA/600)
Seagate Exos X18 Enterprise Class, 18TB, Enterprise Internal Hard Drive, SATA, 3,5" 6Gbit/s, 128MB cache ((ST18000NM000J)
Seagate Exos X10 Enterprise Hard Drive ST10000NM0096 10 TB - SAS 12Gb/s
Seagate Exos 7E8 HDD 512N SATA
WD Ultrastar — Current Prices
New Western Digital Ultrastar enterprise drives sorted by price per terabyte. The Ultrastar HC-series carries on the HGST legacy of reliability.
Western Digital HUH721212ALE604 12TB Ultrastar DC HC520 SATA HDD - 7200 RPM Class, SATA 6 Gb/s, 256MB Cache, 3.5"
Western Digital Ultrastar DC HC550 Enterprise Hard Drive 18TB (3.5" SATA 6Gbps, SAS 12Gbps, 7200RPM, 512MB Cache)
Western Digital Ultrastar DC HC550 3.5" 16000 GB Serial ATA III
Western Digital Ultrastar DC HC550 18 TB Hard Drive - 3.5" Internal - SATA
Western Digital 8TB HGST Ultrastar DC HC320 HUS728T8TALE6L4 * Ent.
Western Digital 6TB Ultrastar DC HC310 SATA HDD - 7200 RPM Class, SATA 6 Gb/s, 256MB Cache, 3.5" - HUS726T6TALE6L4
WD Ultrastar DC HC560 WUH722020ALE6L4 20 TB Hard Drive - 3.5 Internal - SATA [SATA/600] - Conventional Magnetic Recording [CMR] Method,Mechanical Hard Disk
WD-40 Ultrastar HE12 12TB SAS 512E
High-Capacity Enterprise (14 TB+)
The largest enterprise drives from both families. More terabytes per slot means fewer bays, fewer HBAs, and lower power per usable TB.
Seagate Exos X24 24TB internal server Hard drive ST24000NM000C 3.5" HDD SATA3 512MB 7200RPM
Seagate 14TB HDD Exos X14 7200 RPM 512e/4Kn SATA 6Gb/s 256MB Cache 3.5-Inch Enterprise Hard Drive (ST14000NM0018)
Western Digital Ultrastar DC HC550 Enterprise Hard Drive 18TB (3.5" SATA 6Gbps, SAS 12Gbps, 7200RPM, 512MB Cache)
Seagate Exos X18 Enterprise Class, 18TB, Enterprise Internal Hard Drive, SATA, 3,5" 6Gbit/s, 128MB cache ((ST18000NM000J)
Western Digital Ultrastar DC HC550 3.5" 16000 GB Serial ATA III
Western Digital Ultrastar DC HC550 18 TB Hard Drive - 3.5" Internal - SATA
Seagate 16TB ST16000NM001G Exos X16 SATA 6Gb/s 7.2K RPM 512e/4Kn 256Mb, OEM, Mechanical Hard Disk
Seagate Exos X18 Enterprise Class, 16TB, Enterprise Internal Hard Drive, SATA, 3,5" 6Gbit/s, 128MB cache (ST16000NM000J)
Refurbished Exos & Ultrastar
Recertified datacenter pulls from both brands. Enterprise drives are designed for 2M+ hour MTBF, so a drive with 20-40K hours of use still has substantial life — ideal for homelabs and non-critical storage.
Why this matters: Refurbished enterprise drives often deliver the lowest price per TB available. Look for sellers that include SMART reports or a seller warranty. Drives with low reallocated sector counts and under 40,000 power-on hours are typically good candidates.
HGST, a Western Digital Company Ultrastar 7K6000 6000GB 7200RPM SAS 512E Ultra SE 128MB Cache 3.5-Inch Internal Bare or OEM Drives 0F22811
Seagate Enterprise C EXOS X18 10TB 3.5IN 7200RPM SAS Helium 512E
Seagate EXOS X22 22TB Interne Server Festplatte ST22000NM000C 3,5 Zoll HDD SATA 6Gb/s 7200RPM SED 512E 512MB Cache (Renewed)
HGST Ultrastar He10 | HUH721008AL4200 | 0F27406 | 8TB 7200 RPM 256MB Cache SAS 12Gb/s 3.5" Inch | 4Kn | Instant Secure Erase | Helium Platform Enterprise Hard Disk Drives
ST14000NM0048 Seagate 14TB SAS 12 Gb/s (Not SATA) Exos X14 (New with Warranty) 3.5 Inch 7200 RPM 256MB Cache 512e 4Kn Enterprise Hard Drive HDD
Seagate Exos 7E10 8TB Internal Hard Drive HDD - 3.5 Inch 512e/4Kn SAS 6GB/s, 7.200 RPM, 256MB Cache and 2M MTBF for Enterprise, Data Centre (ST8000NM017B)
Western Digital Ultrastar DC HC530 14TB SATA 6Gb/s 7200RPM 3.5-inch Enterprise SED HDD - WUH721414ALE6L1 (Renewed)
Western Digital WUH721414ALE6L4 14TB Ultrastar DC HC530 SATA HDD - 7200 RPM Class, SATA 6 Gb/s, 512MB Cache, 3.5"
Related Buying Guides
Best Enterprise Hard Drives
Compare enterprise HDD prices for Seagate Exos and WD Ultrastar. Datacenter-grade drives sorted by price per TB for servers and storage arrays.
Best Refurbished Hard Drives
Find the best refurbished and used hard drive deals sorted by price per TB. Enterprise pulls, recertified NAS drives, and high-capacity bargains from Amazon US and UK.
Best HDD Deals Right Now
Live hard drive deals ranked by price per terabyte. New and refurbished HDDs on Amazon US & UK — prices checked every hour so you never overpay.