Negative Case Pressure

[OffDutyBarista]

I have an am900z that I've been slowly building on, but I'm having an airflow problem. I have 3 corsair 120mm LL in the front at full rpm with one in the back for exhaust and I moved the fan that the case came with to the top. I've tried adjusting the speeds of the fans multiple times but the extra gpu slots in the back (you get what I mean) seem to want to always suck air in. Any advice or help?

[WereCat]

3 minutes ago, OffDutyBarista said:

I have an am900z that I've been slowly building on, but I'm having an airflow problem. I have 3 corsair 120mm LL in the front at full rpm with one in the back for exhaust and I moved the fan that the case came with to the top. I've tried adjusting the speeds of the fans multiple times but the extra gpu slots in the back (you get what I mean) seem to want to always suck air in. Any advice or help?

Do the fans in front of the case even do something? On the images I see no way for the air to get inside from the front.

[WoodenMarker]

With such a restrictive front panel, you'll probably need more intake fans to prevent air from coming in the rear. 

Why did you move the fan to the top?