Windows 8: Graphics performance really low

[MrKiko]

Hello, I'm a Windows 7 user since years. In last months, I tried few times to upgrade my OS to Windows 8 and 8.1 but due to the low graphic performance that I've got, I always came back to Windows 7.
My config is: i7 920 @2.67GHz - AMD HD5850 1GB - SSD Samsung 840 - 4 GB RAM 1333MHz

To be sure it was not just an impression, I installed and launched 3DMark Sky Diver 1.0 in both OS. Here the result

Windows 8.1: 6.382 scores -> Graphics score: 6.757 - Physics scoree: 4.336 - Combined score: 9.022

Windows 7 Ultimate: 7.517 scores -> Graphics score: 8.708 (+28% compared to W8) - Physics score: 4.199 - Combined score: 8.947

Looking this result, it's clear how CPU (physics) works also better on Windows 8.1 but the graphic score is really worst.

About games:
GTA San Andreas from 300-350 FPS on Windows 7, I can reach just 150 on Windows 8.
Minecraft: A lot of problems on Windows 8.1 in some places where on Windows 7 is perfect
Tera Online: Pretty unstable FPS rate on Windows 8.1

I have no idea why I have this poor GPU scores on Windows 8 or Windows 8.1 (same on Windows 10 Technical preview)

I don't know what to do, I really want to upgrade my system to Windows 8.1 but I can't due to that bad performance.

The Graphics driver installed are the same on both OS -> Catalyst 14.9 - 14.301.1001-140915a-176154C

I also checked the temperature on both OS. On Windows 8 I have like 5-6°C more

The only problem I found surfing the internet is about mouse lag in some games (That I have too) but anything about this really painful scores. I hope someone can help me!

Thank you for any reply!

 

[velo3100]

I think it is the type of games. Windows 8 and 8.1 are not good with old games. I have the same issue with tera onine. My gpu will fluctuate in fps and it is more than capable to play it. There is not much you can do that I know of until microsoft sorts out this issue. I would stick with 7 and wait until 10 is officially out as it should be able to improve performance. You also may want to upgrade the ram to 8.

 

[Xibyth]

My GTX 770 has trouble with Tera and their awful Flash Player UI. You may look into a RAM upgrade. Many people still advocate the 4GB is enough deal, but the reality is unless your only browsing the web, its not. Go for 8.

As for Windows 8.1 I had some issues with Java and minecraft but otherwise I have not had any issues. Other than that I love my 8 second boot from a cold startup.