T30 Wireless problems (3rd card so far)

Ok, I've had my t30 for about a year now, when i first got it I found that sometimes the wireless would simply stop working after a while, a restart got it working again for a while. I later upgraded my card (after running the software to get rid of that annoying non-approved card error) to a wireless G card I pulled out of an bad and old linksys wrt54g 1.0, for a few months that worked fine then started having connection issues as well, disconnects and such, So, I ordered an Atheros based a/b/g card which also worked fine for several months and is now having the same issues. My particular T30 has several slots on it's mini pci cover positioned directly below the fan. I have seen pictures of other T30's on ebay and elsewhere that DO NOT have those same slots. I'm starting to suspect because the fan is directly in line with those holes that it is pulling all it's air from those holes and thus not drawing it through the laptop itself and I'm thinking because of that the wireless card is getting hotter than what it can withstand longterm and that they are failing due to the elevated heat levels, my memory cover/hard drive area also gets quite warm. I have done some other upgrades to this system, such as swapping in a 2.2 ghz cpu rather than the 1.8 I had, (I bought from ebay the other fan part# for the faster fan and used arctic silver) but one thing I noticed is my original fan had a small piece of foam in it for the vent in the rear of the system and the "upgraded" fan did not, I'm not sure if that's normal or not.

So, does anyone think this might be the cause of the problem, that the holes keep it from drawing air through the entire laptop?

Or if people can get on and say wether or not their t30 has those holes and wether or not they are having problems with their wireless.

I'm including a picture of the cover.