help with power supply option

[Axxion V]

hi! hope i joined the right place here. anyway i have a question about a psu option i couldnt find an answer to in search. first off my specs are:

windows xp pro.. will get 64 bit soon but now 32 bit
biostar ta790gx
athlon x2 5600 2.9ghz sometimes oc'd to 3.05 when it's cool in my room
4 gb ram
2x 80gb hdd raid 0
cd/dvd combo drive
all in wonder hd
420 watt psu

ok so im upgrading my graphics card. im still searching and deciding on that but im going at least hd 3870 CF or 3870 x2. seems i can get 1 or the other for around $120. i know i need more power. well i found a dedicated graphics card psu. (same as this one here VISIONTEK 450 Watt Dedicated Power Supply : Spare Parts | Dell ) i can get this thing for $30 with my jobs employee discount. so i will only be using the dedicated 450 watts for the graphics card's only and combined with my 420 watt i will have a total of 870 watts? at least thats my understanding but i wanted to check with some tech gurus before i went through with it all. any advice will be appreciated.

 

[carnageX]

Just get a whole new power supply... You can get a high quality Corsair PSU for the same price as that dedicated PSU, which IMO isn't worth it...

Modular one: Newegg.com - CORSAIR CMPSU-520HX 520W ATX12V v2.2 and EPS12V 2.91 SLI Certified CrossFire Ready 80 PLUS Certified Modular Active PFC Compatible with Core i7 Power Supply - Power Supplies
Non-modular: Newegg.com - CORSAIR CMPSU-650TX 650W ATX12V / EPS12V SLI Ready CrossFire Ready 80 PLUS Certified Active PFC Compatible with Core i7 Power Supply - Power Supplies

 

[Axxion V]

thanks for the feedback. keep in mind i can get the dedicated for $30. seems like a good deal to me if the combined watts = 870.

 

[Axxion V]

any other opinions on this? is 450 watts dedicated ok if it's dedicated to just the GPU/s? will that be ok for some newer cards?

 

[Burn]

i would just get a whole new PSU all together. either the 650tx that carnage recommended or the 750tx.

 

[Muffin Man]

it seems like youre just looking for confirmation that the dedicated psu will work. i dont know if many people here have used something like that, but it doesnt seem to offer any other info (like amps) besides the description that claims it supports quad-sli...

 

[Axxion V]

thanks again for the feedback. well despite recommendations i bought the dedicated psu. i ended up paying $40 for it. i made this decision because by only spending $40 i can now afford an xfx 4890 xxx. i will post back how it all works out.

 

[scrimstar]

420 watts wont cut it for the 1890.. I think.

 

[carnageX]

Its not wattage that count as much as amperage on the 12v rails.

 

[Axxion V]

ok well this website ( Radeon HD 4890 review | test ) says the hd 4890 requires 16 amps per card. on this forum ( Will my current dedicated power supply run a GTX 295? ) the guy states he owns a VisionTek 450 Dedicated PSU and it puts off ~38 Amps over 2 +12V rails. So how does that sound?