So if I don't need more than 1-3 mins back up time (or not even that), but want a pure sine wave, would going for a cheaper APC UPS with 800va be sufficient? or does it really have to be a 1500va one even if I don't need 10-20 mins backup time?
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The electrical buzzing sound is normal right?
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So if I don't need more than 1-3 mins back up time (or not even that), but want a pure sine wave, would going for a cheaper APC UPS with 800va be sufficient? or does it really have to be a 1500va one even if I don't need 10-20 mins backup time?
You could. I'd probably go for 1000VA as a minumum, but tend to go for the 1500VA mark due to battery age = time is reduced as they get older (can't deliver the same amount of current as they can when new, just like car batteries).
What exactly does having an "impure" sine wave do? does it cause high pitch noises in electronics?
It can actually damage your equipment.
But noise is another possible issue as well.Good point, I was unclear. I meant that I didn't know the wiring from room to room. I pay the electric bill to a separate company and we do have our own meter. So none of you other MP owners can hear a buzz at very close range?
I'm not using a UPS yet, and at default fan speed, my 2009 Quad MP is absolutely silent sitting on my desk, a foot and a half away from me. I can barely hear the fans running when I put my ears right up to the grill where the two fans are in front. If it wasn't for the display and the white light on the Mac Pro, I wouldn't know it is on sitting 1 and a half feet away.
What about the back near the power plug as the OP mentioned? I agree, from the front, it is nearly silent for me as well. Thanks for trying this out
What about the back near the power plug as the OP mentioned? I agree, from the front, it is nearly silent for me as well. Thanks for trying this out
Hello Dissolve, the back is same as the front, can't hear anything unless I put my ears right to it. All I hear is the fan spinning (wind and motor bearing noise), nothing electronic. Now if I crank the MP fans to max, it sounds like an airplane taking off.
Hello Dissolve, the back is same as the front, can't hear anything unless I put my ears right to it. All I hear is the fan spinning (wind and motor bearing noise), nothing electronic. Now if I crank the MP fans to max, it sounds like an airplane taking off.
Thanks for checking it out. I just tried it again and only heard fans as well. Maybe it's all in my head
Either way, gonna start reading about UPS choices now.
I just repeated the procedure that 2contagious went through: figured out which outlet were on the same circuit as the MP, turned off everything besides the computer, and still get that buzzing. It's faint, intermittent, and sometimes has a weird pulsing to it.
I wanted to echo a previous question: would a simple unit like the APC Line-R that only modulates the electricity, but provides no battery backup, suffice and eliminate this noise? I'm currently not too worried about power outages as I honestly cannot remember the last time we've had one here. Or does it seem I have a faulty power supply and need to contact Apple? I'm still under warranty so that's an easy option (besides the commute to an Apple Store).
I wanted to echo a previous question: would a simple unit like the APC Line-R that only modulates the electricity, but provides no battery backup, suffice and eliminate this noise? I'm currently not too worried about power outages as I honestly cannot remember the last time we've had one here. Or does it seem I have a faulty power supply and need to contact Apple? I'm still under warranty so that's an easy option (besides the commute to an Apple Store).
Just wanted to report back that I took mine in to the Apple Store with that electric buzz and the tech confirmed that it's definitely not normal. They are ordering a new PSU and should have it installed in 1-3 business days. Was a very good experience
Just wanted to report back that I took mine in to the Apple Store with that electric buzz and the tech confirmed that it's definitely not normal. They are ordering a new PSU and should have it installed in 1-3 business days. Was a very good experience
So they were able to reproduce the buzz at the apple store? I have contacted my apple rep and she's exchanging my mac pro again. If this third Mac Pro still has issues, I will either get a refund or get the PSU fixed at the store. Please let me know if the new PSU they will be putting in your Mac Pro makes any difference
Also, are you from the UK? I'm wondering if this might be a voltage related thing.
So they were able to reproduce the buzz at the apple store? I have contacted my apple rep and she's exchanging my mac pro again. If this third Mac Pro still has issues, I will either get a refund or get the PSU fixed at the store. Please let me know if the new PSU they will be putting in your Mac Pro makes any difference
Also, are you from the UK? I'm wondering if this might be a voltage related thing.
Yes he was able to reproduce the buzzing sound in store so it must not have been the circuitry in my apartment. I'm still surprised they replaced your entire machine, but hopefully third time's the charm
I'm in the US so it seems more like a 'bad batch' kind of thing since it's so sporadic between users (at least on these and Apple's forums). I'll certainly report back once they get the new one in.
Yes he was able to reproduce the buzzing sound in store so it must not have been the circuitry in my apartment. I'm still surprised they replaced your entire machine, but hopefully third time's the charm
I'm in the US so it seems more like a 'bad batch' kind of thing since it's so sporadic between users (at least on these and Apple's forums). I'll certainly report back once they get the new one in.
Bad batch of PSUs? I don't know :/ the buzzing PSU issue was also present in some 08 and 09 Mac Pros (google buzzing mac pro).
Just wanted to report back that I took mine in to the Apple Store with that electric buzz and the tech confirmed that it's definitely not normal. They are ordering a new PSU and should have it installed in 1-3 business days. Was a very good experience
That's good to know! Was it the first time they ever saw a Mac Pro?
You're right. I meant that it's not an issue for all models. Not sure where the issue comes from, but it can't be localized to one region. Plus, many here have attested that there's is silent so I guess we just got unlucky
That's good to know! Was it the first time they ever saw a Mac Pro?
Haha I'm not sure, but I got tons of looks walking through the mall and into the crowded Apple Store. That thing is heavy!
My machine sometimes (rarely) buzzes somewhat loudly when the vibration from the hard drives happens to rattle the case just right. Usually moving the machine a little stops the buzz, or tapping the side.
Just saying, this may be the cause of some of your buzzing issues as well.
Just saying, this may be the cause of some of your buzzing issues as well.
It's not just about filtering out surges, it's about being able to shut down your Mac gracefully and not have the power just cut off. Of course that way you won't lose whatever you were working on, but far more importantly, i've seen more computers fried in my time when there was a power outage or someone kicking the cable out or accidentally stepping on a power strip than any other cause.
I wouldn't even think about running my Mac Pro without it. With all of the money you invested in it, a couple of hundred bucks is a small price to pay for the protection you get.
Multiple PSU suppliers and cost cutting are strong candidates.You're right. I meant that it's not an issue for all models. Not sure where the issue comes from, but it can't be localized to one region. Plus, many here have attested that there's is silent so I guess we just got unlucky
Multiple PSU suppliers and cost cutting are strong candidates.
So I happened to get two mac pros with the same crappy psu? :/
It's quite possible, as there's a good chance both systems were made close enough together that the PSU's were from the same manufacturer and batch.
It's quite possible, as there's a good chance both systems were made close enough together that the PSU's were from the same manufacturer and batch.
I hope that the next replacement will at least not come scratched (my replacement Mac Pro has a manufacturing mistake/scratch on the anodised aluminium at the back). If the second replacement still has the buzzing PSU, I'll keep it, but get the PSU exchanged at an Apple store like dissolve. I just hope that doing this will fix dissolve's issue and then mine, too. Already got everything installed on my SSD, ready to be taken from this Mac Pro and put into the final replacement unit. Thank god I don't have uni yet, otherwise this replacement game would suck even more.
I'm not sure if the issue is how long you can run things but how many devices you can have protected and plugged into it.