Hard Drive Failure?

I'm posting here as I don't know where else to go.

After accidental damage to my Alienware 17 R5 laptop I sent it back to Dell for repair. I received the laptop, and everything was working fine for a day or two, until suddenly I tried to boot up and the boot was VERY slow and ended up going into a boot loop. Sometimes, however, it boots up totally fine. Running diagnostics from the BIOS indicates a hard drive failure, but the laptop had just been serviced, and the HDD is new. Running diagnostics through Windows shows that everything is fine. Other posts with a similar problem say this type of thing happens due to bad cables or motherboard, but I've sent the computer in for repair twice and I imagine that's something they would have found and fixed. I'm not very good with this type of thing, but it might have to do with the original HDD having a caching SSD whereas this new HDD has no SSD. Thanks in advance for your help


The detailed report:

AlienAutopsy Log File
Wednesday, April 16, 2014 7:55:55 PM
Overall Test Result: Passed


----------------------------------------------------------------------------------------------------------------------------------------------------------
ATA WDC WD7500BPKX-7 SCSI Disk Device [SCSI:0:0:0:0\\?\scsi#disk&ven_ata&prod_wdc_wd7500bpkx-7#4&2c8d1614&0&000000#{53f56307-b6bf-11d0-94f2-00a0c91efb8b}]
----------------------------------------------------------------------------------------------------------------------------------------------------------

Vendor: Western Digital
Model Number: WDC WD7500BPKX-75HPJT0
Serial Number: WD-WX71EB3L9748
Firmware Revision: 01.01A01
Size: 698.6 GB
Rotation Rate: 7200 RPM
Cache Size: 16 MB
Temperature: 42 C
Physical Sector Size: 4 KB
Logical Sector Size: 512 B
Logical Sector Count: 1465149168
Supported Standards: ATA8-ACS, ATA/ATAPI-7, ATA/ATAPI-6, ATA/ATAPI-5

----------------------------------------------------------------------
OS - C: [PARTITION:C\\?\Volume{4ef3eb1b-c144-11e3-9f70-806e6f6e6963}\]
----------------------------------------------------------------------

Volume Serial Number: 4C23-AFE4
File System: NTFS
Volume Capacity: 688.40 GB
Volume Free Space: 485.52 GB
Volume Used Space: 202.88 GB




SMART Status Test

Test Started - 4/16/2014 7:49:19 PM

Test Finished: - 4/16/2014 7:49:21 PM
Passed

SMART Thresholds Test

Test Started - 4/16/2014 7:49:21 PM

Test Finished: - 4/16/2014 7:49:23 PM
Passed

Targeted Read Test

Test Started - 4/16/2014 7:49:23 PM

Test Finished: - 4/16/2014 7:49:25 PM
Passed

Random Seek Test

Test Started - 4/16/2014 7:49:26 PM

Test Finished: - 4/16/2014 7:50:26 PM
Passed

Funnel Seek Test

Test Started - 4/16/2014 7:50:26 PM

Test Finished: - 4/16/2014 7:52:02 PM
Passed

SMART Short Self Test

Test Started - 4/16/2014 7:52:03 PM

Test Finished: - 4/16/2014 7:54:15 PM
Passed

Linear Read Test

Test Started - 4/16/2014 7:54:15 PM

Test Finished: - 4/16/2014 7:54:20 PM
Passed

Linear Read Test - 2

Test Started - 4/16/2014 7:54:20 PM

Test Finished: - 4/16/2014 7:54:29 PM
Passed

SMART Thresholds Test - 2

Test Started - 4/16/2014 7:54:29 PM

Test Finished: - 4/16/2014 7:54:31 PM
Passed

Product Version: 3.5.6426.22