Aspire 9300-5620 drops wireless connection

Hi this is my first post on this form. I have an Acer Aspire 9300-5620. I bought in either December of 2006, or December of 2007. I bought it off a guy on Ebay who got it as a Christmas present, but decided to sell it AFTER he registered it with Acer. Consequently, since I am not the original owner I didn't qualify for Acer tech support.

But up until recently, the unit has been unbelievably trouble free. It was originally loaded with Vista Home Premium, but according to the original owner the recovery cd(s) were lost, and I was unable to get a replacement from Acer.

About 12-18 months ago, I picked up a virus that I couldn't get rid of, so I took it to the guy who did my repairs when I couldn't figure it out for myself. He suggested, and I agreed to a complete back up, and then a reformatting of the hard drive, and substituting Windows 7 Ultimate in place of Vista Home Premium.

Since doing this the machine has been as reliable as ever.BUT, about three weeks ago my wireless connection was dropping about five, or six times a day. I was always able to reconnect but it was very frustrating. So, I decided to do something about it. My DSL service is through ATT. I called them, told them what my problem was, and after about an hour was told by the tech helping me, that she couldn't figure it out, and arranged for a field tech to come out. He asked a lot of questions, and after testing the lines coming into the house also stated that he wasn't sure what it might be, so he changed out the modem we had for another. After he left I was still experiencing dropped Internet connections, but not as many. I called ATT tech support again, and after another hour troubleshooting was told by the tech that the problem lay not, in the connection coming into the house, nor, with the modem. I was told that the problem lay in the computer's built in wireless adapter. More specifically in the driver for the adapter itself. I was skeptical, but I followed his advice, and went on line to the Acer web site, and looked for the drivers I was supposed to need. I was unable to find the driver, and as a result I tried to ask Acer itself. I had to put my serial number onto the page in order to be admitted to ask questions. But once again, the web site refused to help me because the machine is out of warranty, and if I wanted to pay for it their fees start at $99.95, and go up from there.

So, my question is this, does ATT's diagnosis of an outdated driver dropping the connection sound plausible? If so, please tell me where I can download current drivers. If not I am open to suggestions as to what is causing this.

Thanks
Cliff Harmon