The only thing in my Antec 300 HD cage is a single HD in the bottom, both fans have a straight and clear path into the case.
Right, I have just replaced the two AP's with Silent Eagle 1000rpm's in the front of my Antec 300. Man the quietness is joyful! However, the temps under a Furmark run rise almost exactly in line with the increase in the ambient temperature.. - With two 1450rpm Gentle Typhoons, the inner GPU maxed at 77C and the outer GPU maxed at 62C with an ambient of 20C. - With two 120mm Air Penetrator's, the inner GPU maxed at 76C and the outer maxed at 61C with an ambient of 21C. This was the same result when using 9.5v resistors to quieten them down as well. - Tonight, with the two Silent Eagle 1000rpm's, the inner maxed at 80C and the inner maxed at 65C with an ambient of 24C. As mentioned above, the increase aligns almost exactly with the increase in the ambient temperature. After the Furmark run last night with the AP's, I had a BC2 session and the inner GPU never went above 62C. I think I'm going to leave the Silent Eagles in for now. Edit: Just had a BC2 session, inner GPU maxed at 70C, outer at 56C, ambient 24C.