Drives Fails Quick Test, Pass Extended Test [WDC WD3200AAKS-00L9A0]

I’m a bit confused on why my drive would fail the quick test but pass the extended test. I used LifeGuard to check the drive after SMART failed on startup and came up with these results…

Test Option: EXTENDED TEST
Model Number: WDC WD3200AAKS-00L9A0
Unit Serial Number: WD-  
Firmware Number: 01.03E01
Capacity: 320.07 GB
SMART Status: PASS
Test Result: PASS
Test Time: 03:35:07, July 20, 2012
Test Option: QUICK TEST
Model Number: WDC WD3200AAKS-00L9A0
Unit Serial Number: WD- 
Firmware Number: 01.03E01
Capacity: 320.07 GB
SMART Status: PASS
Test Result: FAIL
Test Error Code: 06-Quick Test on drive 1 did not complete! Status code = 03 (Fatal or unknown error), Failure Checkpoint = 98 (Unknown Test) SMART self-test did not complete on drive 1!
Test Time: 03:37:19, July 20, 2012

I also ran HD Tune to check the health and  to check for bad sectors. Scans found no bad blocks.

HD Tune: WDC WD3200AAKS-00L9A0 Health

ID Current Worst ThresholdData Status
(01) Raw Read Error Rate200 20051 1873 Ok
(03) Spin Up Time 162 131 21 2875 Ok
(04) Start/Stop Count 99 99 0 1825 Ok
(05) Reallocated Sector Count 200 200 140 0 Ok
(07) Seek Error Rate 200 200 0 0 Ok
(09) Power On Hours Count 84 84 0 12098 Ok
(0A) Spin Retry Count 100 100 0 0 Ok
(0B) Calibration Retry Count 100 100 00 Ok
(0C) Power Cycle Count 99 99 0 1594 Ok
(C0) Power Off Retract Count 200 200 0 109 Ok
(C1) Load Cycle Count 200 200 0 1825 Ok
(C2) Temperature 109 98 0 34 Ok
(C4) Reallocated Event Count 200 200 0 0 Ok
(C5) Current Pending Sector 200 200 0 0 Ok
(C6) Offline Uncorrectable 100 253 0 0 Ok
(C7) Ultra DMA CRC Error Count 200 200 0 0 Ok
(C8) Write Error Rate 100 253 0 0 Ok

Power On Time : 12098
Health Status : Ok

HD Tune: WDC WD3200AAKS-00L9A0 Error Scan

Scanned data : 305122 MB
Damaged Blocks : 0.0 %
Elapsed Time : 0:35

I got the drive back in 2008. It has been used as a OS drive for about 3 year [heavy gaming] then a secondary drive for music and movies. Should I be worried? I have all my data backup to an external drive just incase the drive fails on me. Any information about the drive and the results would be appreciated. 

Did you tried running the quick test more than once?

I ran the quick test multiple times before I ran the extended test. The quick test were the same as the results I posted. I noticed that on startup during POST the hard drive fails SMART but it’s not every time. It seems only to fail SMART on a cold boot. Not sure if that information helps.