WoW, I see vastly and completely opposing opinions on this subject, so let me chime in. I'll also add that many consider me an expert, I make no such claim, but I have flashed middletons bios on close to 100 systems in the past 6 months, and I have experienced the worst possible result.
1st issue: as George states, I too trust middleton's bios. It's a genuine lenovo bios with some very minor modifications, so it's entirely safe to use as long as it installs properly.
2nd issue: Windows XP is probably the worst OS to install from. A 32bit vista or seven would be a better option, they are more stable and less chance of a BSOD, which will kill your board and I have seen a bios flash cause BSOD on winXP more then once.
3rd issue: The bootable cdrom disc is a poor design. It has no prevision for a system being unstable. If I was designing it it would have a prompt with a warning saying something like... "Continue only if your system appears stable and you're not experiencing abnormal disc read activity". I've read opinions that it's safer to flash from a boot disc and did so, the boot disc loaded, the drive made some abnormal clicking and repeated scanning noises, obviously having read errors and retried many times, but dispite these errors it continued to destroy my bios just like a soldier marching into cannon fire as ordered, knowing full well certain death would follow. Basically if you have a perfect optical drive, and a perfectly burned disc, then it may be a safe option, but I prefer to flash from a STABLE running operating system. WinXP will do, but I prefer vista or seven.
One thing you NEVER want to do is flash a freshly built system, that's foolish, always use it for days/weeks. When I build a system, I always flash the board before I pull it from the donor machine (if possible), if not, I run the machine for a few days to make sure it's stable before flashing the bios. Also, if I'm going to destroy a board, I'd rather have it happen before I build the system, not after. In the former, I'm out a board, in the latter I'm out a board and a huge amount of time and effort.
In regards to harddrive performance, you will have improvement on any SATA2 harddrive, be it 7200 or 5400rpm, but you probably won't "feel" the difference. The driver RPM speed isn't the only factor when it comes to performance, some people even prefer the 5400rpm drives. Some draw less power and can be a better choice for a portable computer, can take less time to spin up, use less battery, and can even outlast the high speed drive. The rpm rating doesn't effect the speed of data transfer, it's just the rotation speed. Just as you cannot judge a cars performance by how fast the engine revs, you can't judge a drive by how fast the disc spins.
My ideal setup would be an SSD for primary, and a good 5400rpm drive in the ultrabay for storage.
Please understand I'm not trying to contradict anyone's opinion, I respect everyone here and their opinions are valid as much as mine, I'm just telling you what I've experienced and how I feel on the subject, but if you want to cut through all the fluff and get to the core of the matter, then I'll tell you this...
If you're not prepared to accept the possibility of destroying your board, then don't flash your bios!!!
I don't think anyone will disagree with that opinion.
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