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Hi i want to upgrade my 8500gt to an ATI 4670 512mb. the problem i have is i dont think my power supply is good enough as its 5v rail heavy being quite old i think. here is my power supply. i have been told a 4670 needs at least a 450w power supply. however i,ve also been told not to go and buy a 500w from novatech for 17 quid as there are only 15 amps on the +12v rail which is not enough. the next one the y sell is 550w which has 20 amps on the +12v rail. i keep hearing so many things i dont know the truth on this. 20 quid seems a reasonable deal as my budget is very tight due to a new born.

here is my current power supply

Bestec
ATx-250-12z REVc2
Maximum Output 250w
+12v 14A
-12v 0.8A
+5v 25A
+5vsb 2A (not sure what this 1 is)

my system is

Windows 7 ultimate
Amd Athlon II x4 620 processor 2.6ghz
2 gb ddr2 memory (1gb on each stick) (wanted to upgrade this 1 day but graphics comes 1st)
32 bit OS
8500gt (this is what i want to upgrade)
samsung 150 gb hdd
Lg super multi dvd writer.....................other than this the only other things using power is my cheap sound card and my monitor and keyboard.
Question time now..
is my power supply even good enough to run my system as it is? i do experience crashes during games sometimes. will these novatech power supplies do the job? how many watts does my power supply need to be? or is it more down to amps on +12v rail? how many amps does it need to be? is there a way of knowing how many amps, watts etc my pc is using for individual parts? i hope i,ve explained this well enough. maybe sum1 can help me. thanks in advance!

£20 on a PSU. Hmm, well you'd get what you pay for - a piece of junk most likely.

What was it ScottiB said? - about a tenner per 100W will get you a good quality one.


It comes down to quality not quantity about PSU's - you can get a good quality 400W that will run most things yet a generic/cheapo 750W would fail. Buy Corsair or the like (cjeck http://www.awd-it.com - they pretty much sell only decent brand PSU's).

I've no doubt a 400W Corsair would run that system with the new graphics card

i cant understand why the reviews are so good on novatech if there crap in quality. Novatech 550W PSU, link removed as per rules. in theory should a 12+v rail at 20 amps be enough to run my system?

Also i find it worrying how there is no spec info to give amount of amps on different rails. or what connectors it has.
http://www.awd-it.co.uk/scripts/prodView.asp?idproduct=4973&product=Corsair+CX+400W+PSU+Quiet+Power+Supply+-++CMPSU-400CX

http://www.corsair.com/products/cx/default.aspx all the specs you need are here.

The one you mention could be ok - I just doubt it is anywhere near the quality of a corsair one. A lot of the reviews state "good for a budget PC", "great for the money" which it may well be, I'd just want a known quantity if it were me (it is the heart of your PC after all), or an independent review of the PSU by an expert tester (and for Corsair they have been tested by every major PC website there is).

if i brought a psu with 8 pin solid pcie connector and my card needed a 6 pin. what could i do. i know if psu has 6 pin and your card is 8 pin you can get an adapter. using a molex adaptor is no good as it is not made for it. i think i need a 6/8 pin pcie so i got the option but this makes my task harder. on your link it still does not say what connectors i will get. the price is very good though. i heard corsair were good quality to.

It does say what all the connectors are - and pictures of the connectors. There are several tabs on that link page - check out "resources".

I've quickly put your system into a well known PSU calculator - added an extra hard drive and 2 more sticks of memory and a powered USB item just to be on the safe side with 20 % capacitor ageing to simulate a year or so of use:



Swapping out your 4670 graphics for a 4850 gives:



Getting a 20A 12V rail PSU doesn't give you much wiggle room for future upgrades (or for use in a future system).

EDIT: the 8 pin adapters are usually 6+2 arrangement so you can still use it.

your a star. thankyou. so a good branded psu at 450 or 500 should be fine and maybe looking for 30 amps on the 12v rail to be safe. where did you find the calculator and im a div for not seeing the resources tab .lol some of these corsair only have the 8 pcie rather than the 6 and 2 connector. just need to choose one now. i think around 50 quid will be my budget now. so yeh like you originally said 10 quid for every 100 watt otherwise to cheap and to good to be true.

the cx400w on nova says its 8 pin pcie on other models its the 6+2 but on the list you give me on corsair site it says 6 pin but you can clearly see on picture its the 6+2.

Just checked, the cx400 has a 6+2 (I put one in my dad's PC a few months ago) but perhaps, If you are buying now, you should think ahead as you said and look at something a bit future proof and higher rated.

The PSU calculator is at http://www.extreme.outervision.com/ under "tools" though only the Pro version (which I subscribed to ages ago) has the amps/rails guidance.

Heh - that calculator (or at least a similar one) rates my rig at 636W at full load which isn't bad since I emasured it at a little over 650W during 3DMark

wot psu you recommend. cheers dave.

For the last few years I've always stuck with Corsair - for a relatively future proof build I'd stick a 650W in - unless you end up crossfiring graphics cards or massively overclocking you should be good for a long while.

i might treat myself, best not tell the mrs though. tell her i had 400, lol. is my psu ok for crappy rig at the mo. wont of burned out my cpu or anything. need another 2 gig or ram unless i go 64 bit. least of worries at the mo though and hopefully i might be able to play latest games without crashing with a new card. i wish i had more cash spare. stuck between a hd4670 and a 9600gt. im just looking to get atleast 40 50 fps.

Corsair underrate anyway don't they?

My 450w can achieve 520w for example - or something like that.

Either way they're class PSUs.