How to calculate system wattage

Hi,

I want to add a 2nd HDD to my system but am not sure if i'll need a new PSU. As want to backup my OS on an internal drive (no current plan for RAID). I am pananoid about data loss and keep multiple backups of all my media externally and on a separate system.

Do I need to buy a Energy usage meter or can I calc it manually? A Meter is ~ £20 and a good 550w PSU is £55-60 so would seem a waste to get a meter for a one off thing.

The system I want to add to is a Factory built Dell 530 Inspiron:-

Q6600 Quad
350w PSU
3gb
1x500gb Samsung Spinpoint
1xDVD RW
PCI Firewire Card
1x8800gt OC

As you can see the 8800gt is the reason why I'm not sure if I can push the system any further. I've read the 8800gt can draw 80w when its being pushed

The Truth About Graphics Power Requirements V2 - Graphic Hardware - Forums - www.atomicmpc.com.au


Am looking to add another 500gb Samsung (I think its about 10-15w). Any advice would be most welcome

The hexus review of the 9800GX2 has it running under load and using less than 350W lol, sounds fine to me.

Guessing you can't overclock or anything so it will be fine :) Dell have run 8800GTX systems on their 350 - 380W PSU's.

eXtreme Power Supply Calculator Lite v2.5

as a rough guide...

Its not the wattage you need to be to bothered about its the AMPs and how they are split between the rails.

Quote:

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Originally Posted by pands@scan

eXtreme Power Supply Calculator Lite v2.5

as a rough guide...

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or this

eXtreme Power Supply Calculator - Antec Edition

Basically the same.lol

im running a 8800GTS, q6600, 2 drives, 4gb ram, floppy, 4 fans, optical drives, 3 pci cards - on a 380w. and i overclock the cpu a lil :-$ - but as mentioned above i guess it depends on the PSU and the quality, i wouldn't push mine anymore.

the extreme calculater site gives a good idea i think?

A lot depends on the quality of the PSU.

There are 350w power supplies and then there are 350w power supplies. Most don't provide anything like the power they claim to, especially the cheap ones.

I don't know how good the Dell ones are. Perhaps someone else might be able to say.

Quote:

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Originally Posted by pands@scan

eXtreme Power Supply Calculator Lite v2.5

as a rough guide...

---

As mentioned in the other thread by a few guys (myself included), its way off on some things sadly :(

I've seen a similar system (Q6600 G0 + X1900XT based) pull around 310W from the wall under full load with a meter, so I'd be inclined to say you'll be fine.

In regards to power calculators, in my experience the Antec one is pretty good for equipment running at stock, but is a little overzealous for overclocked kit.

I would guess that Dell have provided a PSU that's fit for the system they provided. You will be adding quite a bit of additional draw, and I would be surprised if the PSU coped with it well.

But will a new PSU fit the case?

TBH I would have thought you would be better off flogging the Dell box and buying a new one.

I've not plugged my meter into my PC in a while but I run the following on a 450W TAGAN PSU.......

Q6600 @ 3.4Ghz
8800GTX overclocked
6 (SIX) internal sata drives
2 Internal 120mm fans
External Exos water cooler (pump/leds/2 x 120MM fans)

Who needs 1Kw PSU's?? ;)

Without the Water Pumps you should have plenty in hand, so it really depends on how much they take, and off which rail.

But that begs the question. As was said earlier, there are 350W PSUs and there are 350W PSUs. If the Dell was an Enermax, Seasonic or Antec Truepower, for instance, then no-one would doubt its ability to handle the load.

Hi,

Many thanks for all the responses, some great info, am so pleased with the quality response level on this site!

Tries out the PSU calculator came in at 359w with 2 HDDs, now I'm even more unsure what to do :-)

Whilst I don't believe the Dell PSU to be up there with the Antec brigade, alot of people on the Dell community believe that Dell underrate their PSU's by 50+ watts just to cover themselves if people start modding and blow out their PSU.

My model had the ability to factory spec 2x HDD in Raid 2xPCI cards, ATI 2600XT and 2xOptical drives + they do supply a 6pin PCI power connector on the 350w model (mine) an all this would run on the same PSU as mine. However a 8800gt is not offered by Dell for this model.

QUESTION - If I overloaded the PSU would this kill components in the PC (processor, mobo)? or would it just kill the PSU??

Think I might buy a power meter and benchmark the PC running a few demanding tasks whilst also running 3DMark06 so I know the Video card is pulling loads of power - does this sound like an idea?

I can post a link to the Dell PSU spec sheet if anyone is still interested.

Once again thanks everyone

Link to the Dell PSU, not very detailed

Removing and Installing Parts: Dell Inspiron 530 Owner's Manual


BTW - Dell box is mATX so wouldn't be hard to replace the PSU

Word on the Dell forums is that it should be fine to add a 8800GT without upgrading the PSU. There even seem to be some calls that their 300W model is up to the task, I guess Dell PSU's must be at the same grade as Shuttle's these days.

A word of caution though, the one shot I found with the card installed has it apparently blocking the second hard drive mount, although it wasn't particularly clear (ebay, scroll down to the pictures).

In regards to overloading PSU's, nothing is certain, you may see system instability or something may fuse/fry, although graphics cards have had long been built to check if they get enough power on boot and will complain if they don't get enough.

Thanks Main, I have checked the 2nd drive bay it will be a close fit (1-2mm from the bottom of the HDD to the top of the card) but I believe that it will just fit.

Just an update, have brought a Power Meter online. Found one for £15 on ebay new thats the same model as one in Maplins for £27. Will know for definate the power draw next week. Could have chanced it, but piece of mind. Will report my results!