I recently upgraded my Aspire M1100 to 1TB Western Digital Blue 7200RPM hard drive. However, I'm getting BIOS error since then. Ok, here's the problem: whenever I boot up the system from a cold start, I would get the following message: BIOS Checksum Error - Defaults Loaded Press Del to enter Setup or F1 to continue. So, I chose to setup my BIOS with my personal settings. After that, it boot up to Windows Vista with no problems whatsoever. In fact, Vista runs just fine as it should. Even when I do a system restart, the system will boot up with no problems. This partcular problem only happens during cold boot. Just to make things clear that I already change the BIOS battery, resetted the BIOS by shorting out my CLEAR CMOS jumper on the motherboard. Also, note that my 1TB has broken into two equal partitions. So, I concluded that my BIOS has corrupted. And since the BIOS is just a piece of chip which can be replaced(in most cases but correct me if I'm wrong here), I sought help from Acer customer service. And just as I thought, I got a "scripted" reply. A customer service officer by the name of Helen(Acer Singapore) told me that I couldn't purchase the BIOS chip as a spare part due to the fact that my model is obselete. Ok, fine I thought. But at least give me a way to download the latest BIOS update for my particular model instead of just "shooing" me away by telling me to look at Acer's FAQs and the download drivers section. Firstly, if I can find the answers there, I wouldn't have contacted Acer in the first place. Secondly, the "download drivers" section used to have a BIOS update for my model previously, but not now. It's no longer available. I just need somebody here to point me in the right direction so that I can have my BIOS flashed and updated so as to confirm that my BIOS is indeed corrupted and in need of an update. If there's anybody here who can help me with my current situation here would be greatly appreciated. My system's serial is PTS890Y0488050005E2702 for reference. Hope that helps. I can provided further details if needed. Thanks! Hope to hear from you guys out here!!