OT: Buzzing on iMac Driven by APC UPS

A specific model number for the UPS would help greatly here, but one thing that instantly springs to mind is that many off-line UPS's use a stepped approximation of AC power rather than a true sine wave. This introduces harmonics that aren't present when running off true AC power. It is possible that these are causing some kind of movement in one of the PSU's magnetic components - most likely a lose winding.

As for how likely it is to cause problems, who can say? I have a hunch it will be fine - if the system appears to work fine on batteries then personally I wouldn't be overly concerned about it

- it is not as if it is going to be running like that for extended periods after all.

AC circuitry isn't my strong point at all but I can't see a trivially simple method of removing the harmonics at the power levels needed for a PC, especially since we are dealing with main voltages and safety is an additional consideration, which would make me even more hesitant of a homebrew solution.

If you are still concerned with the situation return the UPS and replace it with a true sine wave output model, but be warned in advance that these are usually higher-end and consequently pricier units.

Thanks for the info.

That would be my guess/hunch as well.

So far I think the machine is not too shabby. It is a single unit (no separate monitor), and so far, aside for problems with Norton 360, it seems fine (Norton AntiVirus is fine on it, just not Norton 360). I have it set up dual boot for Windows and the Mac OS.

I like the general lack of unnecessary wires.

For general entertainment, here is a video of me pressing the power switch for the first time:

Dave.

I didn't know you could boot windows on a Mac. Is this an actual boot of Windows or does it run in under some interface software?

I would like to buy a new computer, but I don't want Vista and XP is no longer sold... at least in theory. I would stick with Win2k, but I would have to build my own machine if I don't want to pay for Vista only to throw it away. Sounds like maybe I really can get the best of both worlds with a Mac if it will also boot Windows. Any idea if Apple supports drivers for Win2k?

Rick

You can boot Windows XP or Vista natively (i.e. nothing running underneath) or you can use various virtualization options to run it from inside MacOS.

Absolutely not, though you could probably get some basic functionality to work. I use Windows on my MacBook inside the free VirtualBox emulator (as I posted here not too long ago) and it's finally a solution that lets me do my productivity stuff in MacOS while simultaneously running the JTAG pods and other misc. interface hardware and software that are only available for Windows. I haven't actually tested Win2000 in this configuration, but XP certainly works fine, and 2000 is supported.

It is an actual boot of Windows. The Macs now allow you to create a dual-boot system. I can still run Mac OS/X (it has its own partition on the disk).

Bootcamp seems to be nothing more than an Apple version of software to create a dual-boot system. The iMac is an x86 machine ... Windows loads on its own partition, just like installing on a non-Mac machine. I think only Windows+Drivers are involved--nothing fancier.

I originally was considering my options because I wanted to mess around a bit with iPhone development, and the SDK will only run on OS/X.

In any case, here is the sum total of my complaints so far:

a)You need the full (rather than the upgrade) version of Vista or XP (this is because it can't eject the media drive until drivers are loaded and hence can't verify your upgrade-eligible media).

b)Norton 360 didn't work (it locked up during installation). Norton AntiVirus seems fine.

c)The screen brightness can't be winched down enough using Windows:

I will end up buying color calibration software (Spyder2, I think) and messing around with the color map. I may also simply get some of that film they use for tinting home windows.

This is a software, not a hardware thing. OS/X does fine with it.

But I loaded SlickEdit, and a Cosmic compiler on it (including the USB dongle drivers). I also have MikTeX, Ghostscript, GhostView, SmartDraw, Microsoft Office, and Microsoft project on it. I have no evidence of any type of issue except for Norton 360. Machine seems fine.

According to the Apple documentation, the drivers support only Windows XP service pack something and Vista. There may be more detail here:

I encountered the Wikipedia link for the first time when composing this e-mail. I'm laughing because the technically ambitious community also has tried Linux on it. Why am I not surprised? The iMac has a CD drive. A Linux CD fits in the drive. Somebody was bound to try it.

If you look around the Internet, I also believe you'll find that a few individuals have hacked the crap out of OS/X and gotten it to run on non-Macs. (I am just mentioning this for humor--this is a gross violation of the EULA and I'm not suggesting that this is legal or acceptable behavior.)

So, overall, what I'm trying to say is that although Win2K is nominally not supported ... who knows what luck you would have? ... this is a deep dive technical thing.

I'm also going to make the observation that most of the iMac hardware seem standard, so there may be drivers out there.

I hope this information helps.

Except for the screen brightness thing, I'm pretty happy.

Dave.

One more comment ... it sounds to me like you want to run Windows and OS/X both. If this is the case ... then a Mac may be the best option.

But if you're looking for a form factor with computer and monitor integrated, I believe both Dell and HP have them, although not as cool-looking as the iMac. I was in Sam's or somewhere else yesterday and strolled by something that looked like another iMac knockoff, this time from HP.

So, if you're just looking for the form factor, there may be more options.

Further to earlier comments: note that in order to boot directly into Windows on a Mac, you can only use Windows XP SP2 or later (or any version of Vista).

If you have an earlier edition of Windows XP on CD, you have to "slipstream" it to create a boot CD with SP2 preinstalled, and that would have to be done using a different computer.

A Mac won't boot directly into Windows 2000 or earlier, or any of the Win9x or WinME, or MS-DOS.

I'm less familiar with Linux compatibility, but recent Linux kernels should work when booted directly. (They need to support EFI or EFI with BIOS emulation.)

Another option is to use virtualisation software (VMware Fusion or Parallels Desktop) which runs on Mac OS X, and these _will_ let you run older operating systems inside the virtual machine.

In case it isn't obvious: you need a Mac with an Intel processor to do all of this. That's all new models introduced from the beginning of

Note that Apple continued selling one PowerPC model (the PowerMac G5) until the middle of 2006, until it was replaced with the Mac Pro.

If you buy a second-hand Mac, note also that Apple's "Boot Camp" software is needed if you want to be able to dual-boot Mac OS X and Windows, and you only get that as part of Mac OS X 10.5 (there was a beta with 10.4, but it has long since expired).

A second-hand Mac originally sold before October 2007 would have been supplied with Mac OS X 10.4, and you might have to buy a copy of 10.5 ($129 retail) if you want dual booting.

If you only want to run Windows, this isn't an issue.

No. The key problem is that Win2K requires BIOS to boot. The Mac uses EFI, with BIOS emulation, which is apparently sufficient for late versions of WinXP but not for anything older. In addition, Apple only supplies drivers for WinXP SP2 (or later) or Vista.

You could run Win2K inside a virtual machine, in which case you are using the drivers supplied with the virtual machine software. I'm more familiar with VMware Fusion, and it says it fully supports Win2K, though I haven't tried it.