DIGIT-ARC read-only archive · snapshot: July 23, 2026

vx450 & apc

26 posts · originally from https://geek.digit.in/community/threads/vx450-apc.126847/

H
hade123 Original post #1
May 13, 2010 at 10:22 PM
I'm planning on getting a new pc in a couple of days. I've decided on everything except the psu and ups. The more I read about PFC and stuff the more confused I get. Some say their vx450 works with apc (the simlated sine thing) and others say it doesn't and can even be harmful to the system.

Can someone clear up this for me? Would the vx450 work with a APC BR550CI-IN 550VA ups? Also if it doesn't can you recommend a psu and ups combination that work well together? something I can get for around 6.5k?

Thanks
asingh
asingh #2
May 13, 2010 at 11:01 PM
Get a 650 APC. UPS are calibrated to output/support a load of ~65%.

550 rated = 358W support
650 rated = 422W support
H
hade123 #3
May 13, 2010 at 11:12 PM
Hmm, so would a APC BACK-UPS 650VA work fine with a vx450 without any problems or putting my system in danger?
Revolution
May 14, 2010 at 5:58 AM
What is the difference between APC Back and APC Smart series UPSs ?
Why Smart series so costly ?
asingh
asingh #5
May 14, 2010 at 10:06 AM
Hmm, so would a APC BACK-UPS 650VA work fine with a vx450 without any problems or putting my system in danger?

I am using a 1.1KVA APC with my TX650. Been fine. Almost 365 days...!
pulsar_swift
May 14, 2010 at 10:09 AM
I am using a Microtek Heritage 600VA and a VIP GOLD 500W. If i upgrade to a VX 450 will my current UPS support it ?
H
hade123 #7
May 14, 2010 at 12:11 PM
thanks a lot asigh.. going with vx450 and apc 650va
asingh
asingh #8
May 14, 2010 at 12:48 PM
I am using a Microtek Heritage 600VA and a VIP GOLD 500W. If i upgrade to a VX 450 will my current UPS support it ?

600VA = ~ 390W of support.

If you pull greater than this via the PSU, it will not support it. It is not about which PSU you are using, it is about how much your system will draw at load, and is of course within the PSU calibrated limit.
Piyush
Piyush #9
May 14, 2010 at 12:57 PM
600VA = ~ 390W of support.

If you pull greater than this via the PSU, it will not support it. It is not about which PSU you are using, it is about how much your system will draw at load, and is of course within the PSU calibrated limit.
awww man..
i never knew this stuff
it means i have to replace my ups too bcoz i'll be upgrading my rig this june
pulsar_swift
May 14, 2010 at 2:06 PM
600VA = ~ 390W of support.

If you pull greater than this via the PSU, it will not support it. It is not about which PSU you are using, it is about how much your system will draw at load, and is of course within the PSU calibrated limit.


Actually i have two 600VA UPS . 1 UPS is powering the CPU alone and the other one is powering the monitor and the modem, does it make any difference ?
A
May 14, 2010 at 2:11 PM
not much you would be saving 50-100w load from first ups depending on what type of monitor you have.
pulsar_swift
May 14, 2010 at 2:17 PM
Asigh, could you explain the calculation 600VA ~ 390W ?
asingh
asingh #13
May 14, 2010 at 2:42 PM
^^
As a rule of thumb, the efficiency of UPSs' is 65%. So 390W is 65% of 600. Rest of the 'energy' is wasted in heat.
pulsar_swift
May 14, 2010 at 2:45 PM
Ok, If I add a HD 5770 to my current config, what would the total power drawn from a VX 450 ?
asingh
asingh #15
May 14, 2010 at 4:02 PM
Here you go.
R
rajan1311 #16
May 14, 2010 at 7:21 PM
Get a 650 APC. UPS are calibrated to output/support a load of ~65%.

550 rated = 358W support
650 rated = 422W support

Well, not exactly correct terminology, but correct nevertheless .

650VA is the output,but not in watts,but in VA. Output in VA x Power factor = Output in Watts.

For APC UPS, use power factor as 0.6 (according to apc docs).

I have been using a 500VA APC UPS for almost 2 years now,with a VX550. Your system would never use more than 200-250W.

If you get higher VA UPSes, you get a higher peak output and longer battery life, example: if your system somehow draws 300W, the UPS will give an overload warning and switch off in case of a 500VA UPS, even if the mains are alive (no power cut).
asingh
asingh #17
May 14, 2010 at 8:55 PM
^^
Is it not pretty dumb to have a 550W PSU backed by a 500VA UPS..? The day you hit that load your system blacks out, or the UPS starts to whine like crazy..? OP suggested he has a 450W PSU, so I suggested the UPS accordingly -- how would we know how much he will actually pull.

Could you upload the white paper/link which you referred too. Seems interesting.
Piyush
Piyush #18
May 14, 2010 at 9:11 PM
@asigh
u mean the ups rating should around 1.5 times the rating of a PSU?
(just focusing on numbers)
H
hade123 #19
May 14, 2010 at 9:15 PM
^^
... OP suggested he has a 450W PSU, so I suggested the UPS accordingly -- how would we know how much he will actually pull.

Well I think I might as well run this by you guys before I get it. Here's the config.

core i5-750
Gigabyte GA-P55M-UD2
2gb ddr3 kingston (1 more 2gb ddr3 in a couple of months)
palit 9800GT sonic 512MB
2 hdd's - 160gb sata, 80gb IDE
17" monitor - res 1280x1024

The vx450 would be enough right?
R
rajan1311 #20
May 14, 2010 at 10:33 PM
^^
Is it not pretty dumb to have a 550W PSU backed by a 500VA UPS..? The day you hit that load your system blacks out, or the UPS starts to whine like crazy..? OP suggested he has a 450W PSU, so I suggested the UPS accordingly -- how would we know how much he will actually pull.

Could you upload the white paper/link which you referred too. Seems interesting.

Um...well when i got my UPS i had a low end PC,so 500VA was fine, but after all the "moderate" upgrading, the 500VA still serves the purpose, i get a few minutes to shut down my PC, which is fine.

I have never loaded my PC up so much so that i get the overload warning, i have even connected my monitor to the UPS.

anyways, here is the doc, rep (do they have it here?) me for it :p
*www.ptsdcs.com/whitepapers/14.pdf
pulsar_swift
May 15, 2010 at 8:07 AM
Hhm, if its giving 5 mins backup then i will go for VX 550 and i will be using it on 600VA UPS. UPS will run only the CPU. Monitor is connected to a separate UPS
R
rajan1311 #22
May 15, 2010 at 9:18 AM
^yes that would be ideal, i was just sharing my experience to show that it works, but not very well (good enough for me, but not others).
asingh
asingh #23
May 15, 2010 at 9:28 AM
@asigh
u mean the ups rating should around 1.5 times the rating of a PSU?
(just focusing on numbers)

Just remember UPS have 60-65% efficiency. Calculate it from there.
Piyush
Piyush #24
May 15, 2010 at 3:29 PM
Just remember UPS have 60-65% efficiency. Calculate it from there.
I have few questions regarding Thermaltake Power Supply Calculator
1-system type:is that should be single socket for me even if i have quad core cpu?

2-CPU utilization at which time? Should i consider it when at load?

3-In RAM section , by sticks does he mean the available slots in mobo or the installed chips on it?

4-Capacitor aging????
R
rajan1311 #25
May 15, 2010 at 4:19 PM
I have few questions regarding Thermaltake Power Supply Calculator
1-system type:is that should be single socket for me even if i have quad core cpu?

2-CPU utilization at which time? Should i consider it when at load?

3-In RAM section , by sticks does he mean the available slots in mobo or the installed chips on it?

4-Capacitor aging????

1)Yes urs is a single socket mobo, servers have multi socket motherboards (up to 4 ?)

2)Load at worst case - peak

3)The sticks you have installed

4)just put the recommend value...

This is a very rough calculation of the PSU wattage required and not the actual power consumption of the PC.
Piyush
Piyush #26
May 15, 2010 at 7:29 PM
1)Yes urs is a single socket mobo, servers have multi socket motherboards (up to 4 ?)

2)Load at worst case - peak

3)The sticks you have installed

4)just put the recommend value...

This is a very rough calculation of the PSU wattage required and not the actual power consumption of the PC.
thanks anyways
though the last query is still a pain for me