Not being a fan of shooter software, the only thing I would use from FEAR would be any built-in benchmarking segment.
Oblivion has literally been the first game I can recall that I've played that I ever had second thoughts about whether my hardware was capable of handling it. I started a first test here on this XP 3000 PC (Asus A7N8X), with the already named FX 5900 Plain. In the beginner dungeon, everything was particularly dingy and dark, but the frame rate was fine. I did run into an early conflict with the 77.xx series of ForceWare I had, requiring a driver update to even start the Character Generator.
When the new Cooler Master Centurion box arrived, I reassembled the game box from last year {Abit NF7, XP-M 2600 Mobile, a GB of PC 3200 RAM, and a Radeon 9800 XT (which idled at 70 Celcius!)} I needed a separate PCI sound card in order to get the game to start on that PC, and had to back off on the OC setting from XP 3200 core speed, to XP 3000 core speed. The look of the starter dungeon was sharper, more realistic, and everything about the game seemed better.
Comparing the outdoors among four cards that I've tested now, the FX 5900 wasn't great, but the image quality was better than with a GF 6600 GT. I understand that the 6600 GT's 128 MB of onboard RAM caused that, with smaller textures compared to the large textures that the FX 5900's 256 MB of RAM handle. My granddaughter's PC was here about when I got a new X800 XTPE for the game system, and I tested some saves from the game system on her FX 5600 U equipped machine. The indoors look and frame rate was not that much worse than with the faster FX card, and the outdoors was still better looking than with the 6600 GT (especially the water around City Isle), but the 5600 was deathly slow outdoors.
Inside Imperial City, the FX 5900 and GF 6600 GT seem about equal in image quality, with the 6600 GT having a touch better frame rate (the two CPU's are close in performance, but the game box has the full GB of RAM -- this one has half of that). The X800 hasn't hiccoughed anywhere other than staring into an Oblivion Gate (although it runs pretty hot -- Sapphire didn't use a particularly efficient HSF). But the FX 5600 Ultra was standing still in the City, its frame rate was so poor (part of that blame has to be on the XP 2200 CPU). So far, I haven't run any high-demand test with either a low-level FX, or the Leadtek 6600 GT, in the deep woods. My 9800 XT and X800 were fine there, but the FX 5900 literally died in its tracks when the forest became dense.