how important is psu, pc cases, and good cooling

[vikrant1011]

hi
following is the configration of my computer

intel E 6550
motheboard DG33FB
3d card... nvidia 7900 gt
250gb hdd
160gb hdd
dvd writer DL
2gig ADATA dual channel ram
Arctic Cooling cpu fan

what psu should i use for this configration..

i currently have quantum 400watt,, is it enough?
is the output of such smps accurate?
one shopkeeper told me that they saw its 400 but it actually is 250

also plz explain what is the difference between this psu n the others which are much costlier.. and are they worth??

secondly.. the motherboard is atx n by mistake i got a micro atx cabinet. which is a bit small..
the cpu temp is 65 max but the 3d card n motherboard gets a lot hot..
plz help,, what to do.

 

[vikrant1011]

also plz do explain how important is the psu ( in general) ... can a cheeper psu run the system properly??
i understand how important is case cooling but i really dont get the whole point of the psu.

 

[spuddyt]

watts aren't everything in a PSU, number of amps, quality of components all this kind of stuff can add up to make something with enough watts in theory fail dismally in real world situations, therefore I direct you to a certain sticky
http://www.tomshardware.co.uk/forum/243648-10-power-supply
if that and the links it provides doesn't answer your questions, you have very esoteric questions.

 

[dirtmountain]

http://www.hardwaresecrets.com/article/181

 

[bobwya]

Hi vikrant1011

Poor air circulation and overheating components generally leads to instability. So you know computer crashes in the summer when it is put under more stress or if it has been on for a few hours. Also if you do any 3D gaming you are likely to crash the system. With good cooling a system can run for days without a glitch.

An underpowered PSU will probably not even POST. A poor quality PSU will start a system but the system will be especially unstable under load (especially the GPU as this generally draws more power - unless you have an older P4 prescott/smithfield CPU or similar!!). However the real problem with a low quality PSU is that under stress they tend to blow up... If you are lucky the DC voltage surges won't blow out your MB or RAM which are especially vulnerable to damage.

A poor quality PSU is generally only able to supply its rated wattage at 25C so when its under load and reaching 50C internally you start to see problems!! Especially with the line filtering capacitors which may only be rated at 50C... As a comparision Corsair use more expensive solid capacitors in their power supplies rated at 105C!!

Bob

 

[vikrant1011]

hey thanks a lot ppl. i finally have understood what it is..

just one more question.. which psu do u suggest me to use with the above configration..??

thanks in advance
viCky

 

[bobwya]

just one more question.. which psu do u suggest me to use with the above configration..??

But you only really need the wattage you already have but supplied by a better quality PSU, e.g.:
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139003

Refering to:
http://www.xtremesystems.org/forums/showthread.php?t=108088

You will see that all the Corsair PSU range are classed as Tier 2. The VX450 has a single 12V rail which is the ideal arrangement. With multiple 12V rails one rail can be overloaded causing the system to crash even though the total PSU wattage has not been reached (e.g. when hooked up to a single very beefy GPU).

A 450Watt PSU will run a C2D (OC)/ C2Q (no OC) + 4850 tops but will not allow much headroom for expansion above this. This power calculator will give you more idea what wattage different system configurations will require:
http://www.extreme.outervision.com/psucalculator.jsp
Note: its the power on the 12V rail you need concentrate on when using the above calculator.


Hope that info helps!!

Bob

 

[vikrant1011]

hey thanks a lot bob

ur post really helped me a lot..

now i can choose wisely which psu to go for.. thanku

 

[jpbg]

ya go for the 450 watt corsair psu for sure that thing will keep you through even another non crossfire/sli stage and its efficient and has a beastly 12v rail