Instantaneous Performance and Image Quality
As we have already found out, Prince of Persia prefers graphics cards with a high clock rate of the execution subunits. Other technical parameters do not influence the game’s speed that much. This is good news for Nvidia’s solutions whose architecture provides for a high clock rate of the card’s ALUs.
To get more details about the behavior of ATI’s and Nvidia’s architectures in this game we performed another test using an ATI Radeon HD 4870 1GB and an Nvidia GeForce GTX 260 Core 216. To check out the influence of the computer’s CPU on the frame rate these cards were benchmarked on the main testbed as well as with a junior model of Intel’s new CPU series (Core i7-920 with a clock rate of 2.66GHz and a cut-down QPI).
We selected a display resolution of 1680x1050 as the most popular one among gamers today. Then we used Fraps 2.9.8 to record the instantaneous speed of the cards at five combinations of graphics quality settings for 1 minute. Besides, we captured a few screenshots to visually evaluate the difference in image quality between those combinations. Here are the results:
Oddly enough, it is at the highest graphics quality settings coupled with full-screen antialiasing that the CPU influences the performance the most, but only with the GeForce GTX 260 Core 216. The Core i7-965 EE system delivers an average frame rate of 52fps whereas the same configuration but with a Core i7-920 has a frame rate of 44fps only. It is interesting that the overall behavior of the Core i7-920 system resembles that of the system with a Radeon HD 4870 1GB. The GeForce GTX 260 Core 216 boasts a higher top speed, however: 89fps against 65fps. The frame rate is never lower than 25fps, so there is no point in turning 4x FSAA off on these graphics cards especially as these settings ensure maximum image quality. On the other hand, Nvidia’s solution provides a larger reserve of speed and looks preferable here.
The peak, average and bottom speed of the game grows up with every hardware configuration when we turn 4x MSAA off. The bottom speed of the Radeon HD 4870 1GB systems is somewhat lower than that of the same platforms with a GeForce GTX 260 Core 216, but never lower than 45fps.
What about image quality then? You don’t lose much in terms of image quality in many other games if you turn 4x MSAA off as this technique only improves the reproduction of small details such as tree branches, wire fences, cables, etc. Prince of Persia is a difference case, however. It uses cel-shading and every model in it has a thin black outline that seems to imitate an outlining with a pencil. The models are three-dimensions, so this outlining goes along the edges of the polygons and looks worse when the antialiasing is turned off. You can see this easily in the screenshots. The game’s visuals are seriously worsened, so you should not disable 4x MSAA if you’ve got a fast enough graphics card.
The performance benefits are low when you turn off the High Resolution Textures. The cards deliver almost the same speeds as in the previous case. The quality of textures degrades noticeably, though. This especially affects the fine sophisticated patterns on the floor and walls you can see aplenty in this game. Thus, there is no point in using such settings. The CPU doesn’t affect the frame rate here, either.
When the Graphics Quality option is reduced to the Medium level, you don’t lose much in terms of visuals, but the frame rate grows up considerably: the average frame rate can be as high as 200fps whereas the bottom speed is never lower than 70fps, ensuring a huge reserve of speed for graphics cards like Radeon HD 4870/GeForce GTX 260. Of course, these settings are not appropriate for such advanced solutions but may come in handy for weaker products like the entry-level Radeon HD 4670.
The frame rates are impressively high, up to 300fps and more, at the low settings, but the game uses a simplified lighting model and lacks shadows, which makes it far less eye-pleasing than at the Medium settings. On the other hand, we wouldn’t call it downright ugly even then. The game designers have done a good job and you can use these settings on a system with an integrated graphics core or an entry-level card like Radeon HD 4550. Like in the previous cases, there is no difference in performance between the systems equipped with the junior and senior models of the Core i7 processor.
Summing this test up, we can say that the CPU has nearly no effect on a computer’s performance in Prince of Persia if you use at least a junior Core i7. Installing the expensive flagship model of the CPU can increase the average frame rate at the highest graphics quality settings but the difference can hardly be perceived with a naked eye.
When it comes to the image quality aspect, the game’s using cel-shading means that its visuals worsen considerably if you turn full-screen antialiasing off. Therefore you should only disable this option on graphics cards lower than the ATI Radeon HD 4870, GeForce GTX 260 Core 216 or GeForce 9800 GTX+. We can recommend our Medium settings for such cards. There is almost no difference from the High settings but the game runs much faster.