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USP

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May 9, 2008 2:14:51 PM

Hey guys,

I'm sure this thread could go into another section of the forums but when it comes down to it I think the best and brightest scan this section the most. So I've come here with a slightly off-topic post.

I've recently moved and on a few occasions I've noticed that the lights have been dimming and then coming back to full brightness. I'm not concerned about fixing the how/why that happens but am curious whether I should be concerned about the voltage drops effecting my computer. The dips don't happen often or for very long but should I consider purchasing a USP? Would that be the correct protection? I already have a good surge protector but I'm unsure about damage coming from under-volting things.

And on a related note. I have a HDTV being delivered soon, should I also get a USP for it to protect it from voltage dips? Will it matter?

If the answer to either of my worries is yes... what should I be looking for in a USP? Having never purchased one, I'm stuck looking at newegg reviews that I'm not sure really mean anything.

Thanks!

More about : usp

a c 90 B Homebuilt system
May 9, 2008 4:22:20 PM

You're right to be concerned. If you havent seen unusual behaviour from your PC during the "brownout" (or AC voltage sag) you might be OK.
Brownouts are extremely common and can lead to mysterious problems you would never think to blame on the power system.
While a Brownout is the opposite of a surge it can spike the voltages in ways that arent exactly healthy for your PC and still stay under the surge protector clamping threshold. The better surge protectors arent much less expensive than some UPS devices. Budget surge protectors are better than nothing of course.
Your PSU is the first line of defense - it can handle some AC under voltage conditions and still provide the stable DC power your PC needs.
It looks like your OCZ can handle AC ranges as low as 90V AC and still operate. Below 90V and you'd likely see shutdowns of the PC.
Your PSU also has the ability to store up power for about 20ms in case of total loss of AC power. That hold up time is usually enough for a battery UPS to switch over and start providing power.

If you're thinking about an UPS something along the lines of 550VA 300Watt unit would be what I suggest.
Triplite 550VA 300Watt UPS $50 APC BE550VA 330Watt UPS $63
Both have a switch over time from line power to batter power in the 2-4ms range.
They provide around ~3mins holdup time under full load (3D gaming) and ~10mins under typical loads like web surfing, etc.
The both have management software to shut down your PC if you have it running un-attended (which is important to me)

Im not up on all models of HDTV but I know that the models that use the expensive $300 lamps have potential problems with loss of power to the fans cooling those lamps. On the general principal that a UPS is also a good surge suppressor and the price difference between good between the two isnt great I'd suggest the UPS option. Triplite 350VA 180Watt UPS $35 vs APC Personal Surge Arrestor $20 vs Sharp Aquos 32" LCD HDTV 160watts $1000
Be sure to check the VA/Wattage of your model.

May 9, 2008 4:35:09 PM

I'll second what WR2 has to say about brownouts and the damage that they can cause.

A good UPS will be able to protect from over and under voltage conditions as well as frequency variations. I happen to use APC brand and it's monitoring and control software is pretty good. You can adjust the frequency and voltage range at which the UPS will take over.

IMHO, you definately want to protect any expensive component from fluctuations. Just be careful about what you're buying. A simple surge protector does nothing for voltage and frequency variations. Line smoothing components are what you want for that function.

There's also the aspect of dirty power and line noise. That's a totally different aspect and requires a different solution if you want to go that route. Personally, I look at that from the same point of view as gold plated contacts and monster cable - mostly ego related and fattening the salespersons pockets.
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May 9, 2008 4:53:01 PM

Thanks WR2 for getting back to me.

If you don't mind I have some follow up questions for you.

With the PC UPSs, does the wattage of the UPS have to match the wattage of the PSU? As long as the UPS gives me enough time to exit a program and get through a shut down, that'll be enough for me.

With the HDTV. I actually have the APC Personal Surge Arrestor that you linked. Will that be enough or should I throw down for a UPS for the TV as well? I really haven't a clue about any of this (and how it'll effect the health of my systems) but I'd prefer to err on the side of caution. I'd rather spend $100 bucks than risk losing $2500.
May 9, 2008 6:01:11 PM

@Shez
A 650VA (400W) BackUPS from APC should be enough for your system (the one in your signature). The 22" LCD requires around 80W (max) and count on 300W for the system under "game load".

If you want some "room" for future upgrades I'd recommend getting a 1000VA (APC SmartUPS).

It costs alot more but it would have enough power for a GX2 (over 580W).
Another option would be to buy two smaller APC BackUPSes and use one for the PC the other for LCD + HDTV.
May 9, 2008 6:41:33 PM

It has to have enough wattage to power the system divided by the efficiency of the power supply e.g., system load 400W / 80% PSU efficiency = 500W minimum UPS wattage. Your PSU is probably close to unity power factor, so the VA rating is not an issue. As said you need to add wattage for any peripherals you add e.g., modems, monitors, router/gateways etc. I would suggest adding some headroom, at least 100W, for miscalculation and future upgrades. I would get an APC with EMI and RFI filtering.
a c 90 B Homebuilt system
May 9, 2008 7:06:09 PM

piratepast40 mentions dirty power and line noise as another problem and one that standby UPS doesnt correct. The different solution he mentions is an "always on" UPS that does a superior job of conditioning AC power going from the UPS to the power supply. Most of the time though a standby UPS handles what the home users need.

I won't say Andrius is wrong about his estimate of your PCs power requirements but I used the "less than 55watts" for your monitor (based on the NewEgg spec listing and 226BW owners manual) and the PSU Calculator over at ExtremeOutervision which estimated 270watts for your PC. Thats the power draw with everything operating at the same time at full power. Generally most people dont burn DVDs while gaming, etc so not all your hardware is fully powered. You can probably get by OK with the 550VA 300Watt ratings. If there are upgrades in your future (or items in your PC you left off your sig) you may want to step up one model. I use the APC BE550 and my PC (listed under More Informations) isnt so different from yours and it does fine.
May 9, 2008 7:11:59 PM

Thanks everyone for your feedback. A newegg purchase is imminent. I'm going with two UPSs, a beefier one (the APC BE550) for the computer and the smaller one WR2 linked for my TV.
a c 90 B Homebuilt system
May 9, 2008 7:14:04 PM

Did you find out what your new HDTV's actual draw was?
May 9, 2008 8:26:37 PM

The TV I purchased was the Samsung 40" LNT4061F. The manual lists that it'll draw 245 watts. Will the UPS you linked handle the load?
May 9, 2008 8:41:30 PM

WR2 :
I might be wrong, I guess I went for a higher safety margin. 60W sounds right and reasonalble for a 22" screen. My 24" Samsung states 100W (I guesstimated 80W for 2" less). My old rig(config, pc2) had issues (rebooting, failing to boot, freezing on the desktop) with an APC 650VA (estimated at 400W) BackUPS with a CRT screen. When I switched to an LCD the issues all went away.

Now 3 years later sometimes my drives fail to spin up properly. I think the battery is getting old(still holds 10 minutes). The WD 200GB drive that fails to spinup also has a high "sector relocation count" so I'll have to replace it soon (it's over 3 years old so no luck there). The config came to 380W at peak load (I think).
a c 90 B Homebuilt system
May 9, 2008 8:59:47 PM

Shez;
That 245 watts is probably the max draw from cold start up. The continuous draw is probably less but Im not at all confident it would be sufficiently lower that the Triplite 350VA 180Watt UPS would have large enough capacity.
You may have figured that out yourself and are already calling NewEgg to change your order?
Also forgot to mention to look for UPS with replaceable battery - which the APC is that type.

@ Andrius; I might have gone for the higher safety margin if I didnt already have some interesting experiences UPSs over the years. And there are probably some people who DO burn DVDs while gaming.

Have you tried taking the UPS out of the loop and seeing if you have the same HDD issue?

a c 90 B Homebuilt system
May 9, 2008 9:02:31 PM

Shez;
My first clue to your HDTV UPS needs *should* have been your "risk losing $2500" comment
May 9, 2008 9:32:49 PM

Luckily I haven't placed the newegg order yet. I always stop myself and wait for a few more TsH posts just to be sure :) 

So I'd need a UPS with higher wattage than the original post. Would it be overkill to buy two of the same UPSs, one each for the computer and TV?
a c 90 B Homebuilt system
May 9, 2008 9:40:26 PM

The APC BE550 wouldn't be much overkill for the HDTV and another component - Tivo or satellite receiver for instance.
Where are you at on your PC replacement/upgrade cycle? Maybe size PC UPS for your next build. With a fresh battery a UPS may be the longest lasting item in your PC builds.
May 9, 2008 9:56:41 PM

@WR2
I tried it (it's a mixed bag, most times it works perfectly every now and then the error repeats itself) but I fear the damage to the harddrive has already been done. As I've said it's 3 years old so I don't really care all that much... Speedfan's SMART analyzer web report says it has way more poweron hours than average.
I have a "to buy" order for 3 WD6400AAKS waiting for my next paycheck ;) .

@Shez
If you add a DVR in the future you might have to buy it anyway. So I say no. It's not overkill (APC BackUPS 650VA costs $110). If they were so cheap here I'd have three. Sadly they are not.
May 9, 2008 11:03:26 PM

If I'm really only concerned about keeping the voltage steady and not about having the battery power the components for extended periods of time would a Rosewill RU101 http://www.newegg.com/Product/Product.aspx?Item=N82E16842164001 work for my purposes? I realize that it's battery time is really short but I'm really more worried about the voltage dips than actually losing power.
May 10, 2008 12:03:18 AM

Well to be quite honest I have no idea about the quality of their products.
They don't have the best of reputations so I'd try one before you buy.

APC on the other hand is a worldwide IT favourite so you can't go wrong with them (my BackUPS is 3 years old and still holds for 10 minutes).

Try finding some reviews online and see what people think.
May 10, 2008 7:38:01 AM

Rosewill make, or should I say OEM, the bottom of the barrel power supplies so I wouldn't trust their UPSs either. Additionally a 600VA UPS for $40.00 is too cheap.
a c 90 B Homebuilt system
May 10, 2008 1:19:24 PM

For me any UPS that can't have it's battery changed by the user is a major fault. Warranty 1 year vs APC 3 years.
It also surprised me to read that the Rosewill had AVR or Automatic Voltage Regulation (but for 220V version only). Thats usually a higher end option.
Belkin 750VA 400Watts $70 after rebate also has AVR as does Cyberpower 600VA 340Watts $80
I wonder if APC is resting on it's laurels since I dont see any compareable AVR APC units?


May 10, 2008 7:20:51 PM

I'm pretty sure that APC makes consumer grade UPSs on the side, their primary market is the server market. You can get under voltage for more money and under/over voltage protection for a little more money. You get what you pay for.

Obviously, a UPS gives under voltage by default. What I mean is better delivery before the UPS switches to battery i.e., better power conditioning.
May 10, 2008 11:41:56 PM

APC consumer level UPSes are meant for SOHO. The BackUPS is good enough for any desktop PC within it's wattage range. I've had everything from a fuse overload/cable from socket disconnect/1 phase overload/blackouts/lights going dimm slowly and comming back on at random intervals. Nothing makes it twitch. The only thing that got the better of it was my old cheap 17" CRT screen. Everytime I unplugged it from the UPS/PC the PC froze/rebooted.

Do you need AVR in a consumer desktop UPS? Do you see any benefit from it? I most certanly don't see any drawbacks from it's absence. ;) 
May 11, 2008 3:21:50 AM

I never plug in my CRTs to the UPS, too much power draw. I don't have AVR but I would like it. It does drive the price up and isn't critical, but it is nice. I have a 1000VA or 1500VA, I can't remember, that I got for free. I need to get the batteries for it but I have been lazy. It may have AVR as well.
May 11, 2008 1:53:38 PM

The batteris for such a unit are quite expensive.
If it's an APC SmartUPS it most likely has every feature imaginable/needed.
I learned that CRT+UPS don't work together well the hard way. IE buying a new PSU but it didn't help. In the end I figured it out but it took a while. The CRT was a 100W rated (max) unit just like my current 24" LCD. So powerdraw should not have been an issue.
May 11, 2008 3:43:22 PM

I buy my batteries from the Battery Warehouse a few miles away, not from APC directly. So there's no shipping and they are a lot cheaper. The batteries should cost about $15-$20 ea. That's a lot cheaper than a new UPS. I'm sure it was on the LAN room floor because the batteries went bad and they didn't want to screw with it.
!