http://www.eurogamer.net/article.php?article_id=290745

Gears of War 2  Install Size: 6.7GB

Section Tested	DVD Load Time	HDD Load Time
Initial Load	32 seconds	24 seconds
Tip of the Spear (Digging In)	18 seconds	15 seconds
Gathering Storm	29 seconds	29 seconds
Denizens (Scattered)	17 seconds	11.5 seconds
Horde Stage (Avalanche)	16 seconds	16 seconds
Training Grounds (The Basics)	10.5 seconds	9.5 seconds

The Orange Box  Install Size: 4.7GB

Section Tested	DVD Load Time	HDD Load Time
Loading Half-Life 2	44.5 seconds	25.5 seconds
Half Life 2 Save Game - 'We don't go there any more'	47 seconds	15 seconds
Loading Episode 1	38 seconds	22 seconds
Episode 1 Save Game - 'Direct Intervention'	17.5 seconds	17 seconds
Loading Episode 2	40.5 seconds	25 seconds
Episode 2 Save Game - 'This Vortal Coil'	16 seconds	14 seconds
Loading Portal	34.5 seconds	20.5 seconds
Portal Save Game - 'Testchamber 15'	7.5 seconds	6.5 seconds
Loading Team Fortress 2	57.5 seconds	41.5 seconds
TF2 '2Fort' Capture the Flag System Link match	31 seconds	31 seconds

Viva Piñata: Trouble in Paradise  Install Size: 5.2GB

Section Tested	DVD Load Time	HDD Load Time
Loading New Garden	20.5 seconds	16.5 seconds
Moving to Dessert Desert	7 seconds	5 seconds
Quit to Main Menu	20 seconds	16.5 seconds

Grand Theft Auto IV  Install Size: 6.7GB

Section Tested	DVD Load Time	HDD Load Time
Initial Load	46.5 seconds	33 seconds
Starting New Game	26.5 seconds	25.2 seconds
Loading 'Ivan the Not So Terrible Mission'	8.5 seconds	7 seconds
Loading 'Bull in a China Shop' Mission	20 seconds	11.5 seconds

Halo 3  Install Size: 6.3GB

Section Tested	DVD Load Time	HDD Load Time
Sierra 117	46 seconds	53 seconds
Crow's Nest	59 seconds	70 seconds
Tsavo Highway	46.5 seconds	57 seconds
The Storm	52 seconds	64 seconds
Floodgate	54 seconds	64.5 seconds
The Ark	61 seconds	69 seconds
The Covenant	66.5 seconds	78 seconds
Cortana	40.5 seconds	48.5 seconds
Halo	80 seconds	65 seconds

Fable II  Install Size: 6.8GB

Section Tested	DVD Load Time	HDD Load Time
Loading Castle Fairfax	15.5 seconds	11.5 seconds
Loading Home Village	32.5 seconds	24.5 seconds
Loading Old Tomb	17 seconds	10 seconds
Loading Bower Lake	20.5 seconds	14.5 seconds
Loading Bowerstone Market	28 seconds	22 seconds
Loading Bowerstone Old Town	19.5 seconds	16.5 seconds
Loading Rookridge	18 seconds	13 seconds

Mass Effect  Install Size: 6.8GB

Section Tested	DVD Load Time	HDD Load Time
Initial Loading	25.5 seconds	20.5 seconds
Starting New Career	14 seconds	10 seconds
Normandy Quarters	12.5 seconds	10 seconds
Citadel Upper Wards	16 seconds	14 seconds

BioShock  Install Size: 6.1GB

Section Tested	DVD Load Time	HDD Load Time
Welcome to Rapture	19 seconds	17 seconds
Medical Pavilion	32 seconds	27 seconds
Farmer's Market	27.5 seconds	19 seconds
Fort Frolic	36 seconds	28 seconds
Olympus Heights	31 seconds	24 seconds
Point Prometheus	35 seconds	24.5 seconds
Proving Grounds	21.5 seconds	17.5 seconds
Fontaine	15 seconds	11.5 seconds

Project Gotham Racing 4  Install Size: 6.0GB

Section Tested	DVD Load Time	HDD Load Time
Arcade Chapter 1, Event 1	25 seconds	17.5 seconds
Arcade Chapter 2, Event 1	20 seconds	13.5 seconds
Arcade Chapter 3, Event 1	22.5 seconds	14.5 seconds
Arcade Chapter 4, Event 1	26 seconds	16.5 seconds
Arcade Chapter 5, Event 1	20.5 seconds	14 seconds
Arcade Chapter 6, Event 1	25.5 seconds	16 seconds
Arcade Chapter 7, Event 1	22 seconds	14.5 seconds
Arcade Chapter 8, Event 1	23.5 seconds	15.5 seconds
Arcade Chapter 9, Event 1	22.5 seconds	15.5 seconds
Arcade Chapter 10, Event 1	20.5 seconds	14.5 seconds

Call of Duty 4  Install Size: 6.7GB

Section Tested	DVD Load Time	HDD Load Time
Prologue, FNG	15.5 seconds	10.5 seconds
Prologue, Crew Expendable	15.5 seconds	10 seconds
Prologue, The Coup	15 seconds	10.5 seconds
Act 1, Blackout	13.5 seconds	10.5 seconds
Act 1, Hunted	10 seconds	7.5 seconds
Act 1, Shock and Awe	15 seconds	10.5 seconds
Act 1, Aftermath	11.5 seconds	7.5 seconds
Act 2, Safehouse	13.5 seconds	10.5 seconds

120GB vs. 20GB HDD
The Orange Box

Section Tested	20GB HDD Load Time	120GB HDD Load Time
Loading Half Life 2	25.5 seconds	24 seconds
Loading Episode 1	22 seconds	20 seconds
Loading Episode 2	25 seconds	24 seconds

Gears of War 2

Section Tested	20GB HDD Load Time	120GB HDD Load Time
Initial Load	24 seconds	24 seconds
Training Grounds: The Basics	9.5 seconds	9 seconds
Horde Stage: Avalanche	16 seconds	14.5 seconds

基本上硬盘安装可以大幅提升读取速度是肯定的，尤其是橙盒、GTA4等游戏提升相当显著

但其中发现了一个奇怪的个案：Halo 3

Halo 3硬盘安装后速度没提升就算了反而还变的比光盘更慢？

另有20G和120G硬盘读取速度比较，貌似120G快那么一点点，应该是磁密度较高的关系所致