Here thorough some resources have some details to explain which one tops the other.Crysis and BioShock both the games are DirectX 10 compactible.
Crysis
As with Far Cry, Crysis is an open-ended game with many ways to meet objectives. An addition to the previous Far Cry formula is that most weapons may be modified with devices such as suppressors, telescopic sights, and targeting lasers.
The protagonist, nicknamed Nomad, is also capable of selecting various modes in his military prototype "Nano Muscle Suit." The suit is capable of four modes: armor, strength, speed, and cloak. These modes allow him to absorb and heal damage, lift and throw heavy items and enemies, reload and run faster, become invisible and reduce noise output, respectively. Due to the ability of constantly regenerating health, the game is completely devoid of first aid kits. All of these actions, however, use rechargeable energy reserves that power the suit; energy is recharged most quickly while in armor mode.
The suit can be quickly switched between modes using a rapid mouse gesture system, which adds a strong tactical element to combat.
The suit's integral mask has its own HUD, displaying typical data like a tactical map and current energy levels. The view is electronic in nature, shown in-game through things such as a booting readout and visual distortion during abnormal operation. Onboard utilities include a two-way radio, PDA and audio-visual logging capability, with features like image zoom and night vision provided by optional equipment (given by default in single-player).
The artificial intelligence (AI) in Crysis also aims to be realistic and
believable.
Enemy soldiers constantly employ tactical maneuvers, work as squads, hide and
ambush amongst the scenery, and adapt to changing environments and conditions.
AI soldiers will also respond to sound and subtle movements triggered by the
player's movement. While not engaged in combat, the AI soldiers will also
exhibit typical and lifelike behavior, such as smoking, yawning, talking,
urinating, waxing cars, patrolling, saluting superior officers, etc. Sometimes
these actions depend on whether or not the player was detected earlier. If Nomad
has not been sighted in some missions, he can find some enemies sleeping upon
arriving to his destination. In contrast if he has been spotted they will all be
alert.
A review from wikipedia
Crysis was awarded a 98% in the PC Gamer U.S. Holiday 2007 issue, making it one of the highest rated games ever in PC Gamer, tying with Half-Life 2 and Sid Meier's Alpha Centauri. The UK edition of the magazine awarded the game 92%, describing the game as "A spectacular and beautiful sci-fi epic." Gamespot awarded Crysis a score of 9.5 out of 10, describing it as "easily one of the greatest shooters ever made." GameSpy gave it a 4.5 out of 5 citing that the suit powers are fun but also criticize the multiplayer part of the game for not having a team deathmatch. X-Play gave it a 3 out of 5 on its "Holiday Buyer's Guide" special episode, praising the graphics and physics, but criticized the steep hardware requirements as well as stating that the game is overhyped with average gameplay. Gamepro honored Crysis with a score of 4.75 out of 5, saying it was "a great step forward for PC gaming," but criticized the steep hardware requirements.
http://en.wikipedia.org/wiki/Crysis
BioShock
The player takes the role of Jack, who aims to fight his way through Rapture, using weapons and plasmids that give him special powers such as telekinesis or the ability to electrocute foes. Security cameras and foes can be evaded by stealth; alternatively, security cameras and turrets can be destroyed using weapons, or hacked to use them to the player's advantage. Hacking, which is based on the Pipe Dream game concept, can also be used on health dispensers and vending machines to gain extra benefits, and on locks and safes to gain access to the secured contents.
The main resources in the game are ADAM, EVE, and money. ADAM is a mutagen, which allows genetic changes. Quantities of ADAM can be used to purchase plasmids, EVE, and other genetic mutations at special "Gatherers Gardens" vending machines throughout the game. ADAM can be obtained in several ways, most prominently the harvesting of "Little Sisters" after defeating their bodyguards, the "Big Daddies," who are large, heavily armored, genetically enhanced humans wearing diving suits.
EVE acts as fuel for "active plasmids" in a manner similar to magic points in other games, while money allows the purchase of items and ammunition, as well as paying to override security elements, such as bots or turrets.
It is here that morality is implemented as an aspect of the gameplay; the player can chose to either rescue the Little Sisters, or harvest their ADAM. While both choices have their advantages, this element of conflicting morals has an impact on the storyline, and, among other things, on the difficulty of the game itself.
To adapt and advance the character, the player can purchase plasmids, using ADAM. These are grouped under the Combat, Engineering, Active, and Physical technology trees. The "Active" plasmids are abilities that function as alternate weapons; they are powered by EVE, and require activation by the player. The other classes of plasmids, referred to as "Tonics," are passive abilities that work as long as they are selected as equipment ("equipped").
Plasmids are versatile, and can be used by the player both in concert with each other and with the environment to create numerous effects. For example, "telekinesis" can be used on all loose objects: the player can catch and redirect grenades or rockets, hold large objects to form impromptu shields, or use those same objects as projectiles. Other types of plasmids have different practical uses; for instance, using an "electro-bolt" on a body of water electrifies not only the water, but also any beings and machines within it. An element of choice is present: since not all plasmids can be equipped at once, the player must decide which plasmids to use, and which to place in storage.
http://en.wikipedia.org/wiki/BioShock
You play these games, make sure you meet the requirements.
Minimum Recommended
Official System Requirements for Bioshock
Operating System Pentium 4 2.4 GHz (single core) Intel Core 2 Duo Or AMD Athlon 64 X2
Hard Drive Space 8 GB of free space
Graphics Hardware DirectX 9.0c compliant card with 128 MB RAM (NVIDIA 6600/ATI X1300 or better, excluding ATI X1550), Must support Pixel Shader 3.0 DirectX 9.0c compliant card with 512 MB RAM (NVIDIA 7900GT or better) or DirectX 10 compliant card (NVIDIA 8600 or better)
Network Internet connection required for activation
Sound Hardware 100% DirectX 9.0c compliant card Sound Blaster X-Fi (Optimized for EAX ADVANCED HD 4.0/5.0 compatible cards)
Minimum Recommended
Official System Requirements for Crysis
Operating System Windows XP or Windows Vista
CPU 2.8 GHz or faster for XP, 3.2 GHz or faster for Vista Intel Core 2 Duo @ 2.2GHz, or AMD Athlon 64 X2 4400+
Memory 1 GB RAM for XP, 1.5 GB RAM for Vista 2 GB RAM
Hard Drive Space 12 GB of free space
Graphics Hardware 256 MB video memory, NVIDIA GeForce 6800 GT/ATI Radeon 9800 Pro (Radeon X800 Pro for Vista) or greater NVIDIA GeForce 8800 GTS 640MB, or similar
Sound Hardware DirectX 9.0c compliant card
This page is resourced from wikipedia.