WD2002FAEX detected but capacity is wrong

this is the first time i see this - any clues as whats wrong ?

lifeguard also reports a capacity of 1000gb

this is data from hdd sentinel:

Hard Disk Summary
Hard Disk Number,5
Interface,JMicron USB/ATA
Vendor Information,“VID: 152D, PID: 2336”
Hard Disk Model ID,WDC WD2002FAEX-007BA0
Firmware Revision,05.01D05
Hard Disk Serial Number,WD-WMAWP0497295
Total Size,953890 MB
Power State,Active

Logical Drive(s)
Logical Drive,K: []

ATA Information
Hard Disk Cylinders,1938065
Hard Disk Heads,16
Hard Disk Sectors,63
ATA Revision,ATA8-ACS
Transport Version,SATA Rev 2.6
Total Sectors,1953569134
Bytes Per Sector,512
Multiple Sectors,16
Error Correction Bytes,50
Unformatted Capacity,953891 MB
Maximum PIO Mode,4
Maximum Multiword DMA Mode,2
Maximum UDMA Mode,6 Gbps (6)
Active UDMA Mode,6 Gbps (6)
Minimum multiword DMA Transfer Time,120 ns
Recommended Multiword DMA Transfer Time,120 ns
Minimum PIO Transfer Time Without IORDY,120 ns
Minimum PIO Transfer Time With IORDY,120 ns
ATA Control Byte,Valid
ATA Checksum Value,Valid

Acoustic Management Configuration
Acoustic Management,Not supported
Acoustic Management,Disabled
Current Acoustic Level,Default (00h)
Recommended Acoustic Level,Default (00h)

ATA Features
Read Ahead Buffer,“Supported, Enabled”
DMA,Supported
Ultra DMA,Supported
S.M.A.R.T.,Supported
Power Management,Supported
Write Cache,Supported
Host Protected Area,Supported
Advanced Power Management,Not supported
Extended Power Management,Not supported
Power Up In Standby,Supported
48-bit LBA Addressing,Supported
Device Configuration Overlay,Supported
IORDY Support,Supported
Read/Write DMA Queue,Not supported
NOP Command,Supported
Trusted Computing,Not supported
64-bit World Wide ID,0150E04EC15873DF
Streaming,Not supported
Media Card Pass Through,Not supported
General Purpose Logging,Supported
Error Logging,Supported
CFA Feature Set,Not supported
CFast Device,Not supported
Long Physical Sectors (1),Not supported
Long Logical Sectors,Not supported
Write-Read-Verify,Not supported
NV Cache Feature,Not supported
NV Cache Power Mode,Not supported
NV Cache Size,Not supported
Free-fall Control,Not supported
Free-fall Control Sensitivity,Not supported

SSD Features
Data Set Management,Not supported
TRIM Command,Not supported
Deterministic Read After TRIM,Not supported

S.M.A.R.T. Details
Off-line Data Collection Status,Suspended By Interrupting Command From Host
Self Test Execution Status,Successfully Completed
Total Time To Complete Off-line Data Collection,32160 seconds
Execute Off-line Immediate,Supported
Abort/restart Off-line By Host,Not supported
Off-line Read Scanning,Supported
Short Self-test,Supported
Extended Self-test,Supported
Conveyance Self-test,Supported
Selective Self-Test,Supported
Save Data Before/After Power Saving Mode,Supported
Enable/Disable Attribute Autosave,Supported
Error Logging Capability,Supported
Short Self-test Estimated Time,2 minutes
Extended Self-test Estimated Time,311 minutes
Conveyance self-test estimated time,5 minutes
Last Short Self-test Result,Never Started
Last Short Self-test Date,Never Started
Last Extended Self-test Result,Never Started
Last Extended Self-test Date,Never Started
Last Conveyance Self-test Result,Never Started
Last Conveyance Self-test Date,Never Started

Security Mode
Security Mode,Supported
Security Erase,Supported
Security Erase Time,164 minutes
Security Enhanced Erase Feature,Supported
Security Enhanced Erase Time,164 minutes
Security Enabled,No
Security Locked,No
Security Frozen,No
Security Counter Expired,No
Security Level,High

Serial ATA Features
S-ATA Compliance,Yes
S-ATA I Signaling Speed (1.5 Gps),Supported
S-ATA II Signaling Speed (3 Gps),Supported
S-ATA Gen3 Signaling Speed (6 Gps),Supported
Receipt Of Power Management Requests From Host,Supported
PHY Event Counters,Supported
Non-Zero Buffer Offsets In DMA Setup FIS,Not supported
DMA Setup Auto-Activate Optimization,“Supported, Disabled”
Device Initiating Interface Power Management,Not supported
In-Order Data Delivery,Not supported
Asynchronous Notification,Not supported
Software Settings Preservation,“Supported, Enabled”
Native Command Queuing (NCQ),Supported
Queue Length,32

Disk Information
Disk Family,Caviar Black
Form Factor,“3.5"” "
Capacity,“2000 GB (2000 x 1,000,000,000 bytes)”
Number Of Disks,4
Number Of Heads,8
Rotational Speed,7200 RPM
Rotation Time,8.33 ms
Average Rotational Latency,4.17 ms
Disk Interface,Serial-ATA/600
Buffer-Host Max. Rate,600 MB/seconds
Buffer Size,65536 KB
Drive Ready Time (typical),21 seconds
Average Seek Time,? ms
Track To Track Seek Time,? ms
Full Stroke Seek Time,? ms
Width,101.6 mm (4.0 inch)
Depth,147.0 mm (5.8 inch)
Height,25.4 mm (1.0 inch)
Weight,750 grams (1.7 pounds)
Acoustic (Idle),2.8 Bel
Acoustic (Min performance and volume),2.9 Bel
Acoustic (Max performance and volume),3.3 Bel
Required power for spinup,“1,015 mA”
Power required (seek),6.8 W
Power required (idle),6.1 W
Power required (standby),0.7 W
Manufacturer,Western Digital Corporation
Manufacturer Website, http://www.westerndigital.com/en/products

http://www.users.on.net/~fzabkar/HDD/HDD_Capacity_FAQ.html