DatacenterDisk

MDD 20TB vs Seagate Exos

Side-by-side spec and price comparison. Live data from Amazon US.

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Our Recommendation
👑
MDD 20TB SAS 12G 7200RPM Enterprise

MDD 20TB SAS 12G 7200RPM Enterprise wins on both price ($15.50/TB) and warranty (5 years).

Best $/TB: MDD
Best Warranty: Seagate
Best for RAID: Seagate
Full Specification Comparison
Spec
MDD
20TB SAS 12G 7200RPM Enterprise
$15.50/TB
Seagate
Exos X20 20TB SAS
$43.05/TB
Brand
MDD
Seagate
Model
20TB SAS 12G 7200RPM Enterprise
Exos X20 20TB SAS
Series
MDD Enterprise
Exos X20
Part Number
MDD20TSAS25672E
ST20000NM003D
$/TB
👑$15.50
$43.05
Price
$309.99
$861.00
Condition
New
Refurb
Capacity
20TB
20TB
Interface
SAS-12G
SAS-12G
Form Factor
3.5"
3.5"
Drive Type
HDD
HDD
Recording Tech
CMR
CMR
RPM
7,200
7,200
Cache
256MB
—
Sector Size
512e
—
Workload Rating
—
—
DWPD
N/A
N/A
Warranty
👑5 years
👑5 years
Workload Tier
nearline
—
In Stock
Check
✓ In Stock
Buy
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Workload Fit
Workload
MDD
Seagate
NAS Storage
●●
●●
Backup Target
●●●
●●●
OLTP Database
●
●
Cold Archive
●●●
●●●
Virtualization
●
●
AI/ML Storage
●●
●●
Buying Recommendation
Choose MDD 20TB SAS 12G 7200RPM Enterprise if:
  • ✓ You need maximum storage per dollar
  • ✓ You need new-with-warranty for compliance or budgeting
  • ✓ You need high-density storage for bulk/archive workloads
Buy MDD →
Choose Seagate Exos X20 20TB SAS if:
  • ✓ You need 5-year warranty coverage for production
  • ✓ You're building a RAID array and need guaranteed CMR compatibility
  • ✓ You're comfortable with datacenter refurb to maximize savings
  • ✓ You need high-density storage for bulk/archive workloads
Buy Seagate →

Frequently Asked Questions

MDD 20TB offers better value at $15.50/TB vs $43.05/TB - a 64% price difference. Factor in warranty length and workload rating when the price gap is small.

Mixing drives of different models in RAID is not recommended even if capacities match. Different firmware, error handling and seek patterns can cause rebuild issues. Use identical drives within the same RAID group for reliable operation.

Both drives carry 5-year warranties and are built for enterprise operation. Check brand-specific AFR data and Backblaze drive stats for real-world failure rate comparisons.

MDD 20TB is the better fit for NAS storage. It uses CMR recording which is safe for all RAID levels. SAS interface requires a SAS HBA or SAS-capable NAS.