GPU upgrade with my system?

I have an Athlon x2 4800+ (s939), 4gb DDR RAM, a 550w Antec PSU, and a 7800gt.

I want to upgrade to either a 4870 or gtx 260 gpu next month for all the new games coming out. A few questions:

- how big of a deal will my older proc be in playing these games? I do want to upgrade to a Nehalem chip soon, probably in January... but until then, will my current dual core socket 939 hold me back much?

- will my CPU bottleneck my new GPU much?

- Will my 550w PSU handle the new graphics card underload, along with my CPU/RAM/2x optical drives and 6x HDDs? It's a good Antec PSU, and last year I borrowed a friends 8800gt SLI cards when he was gone and plugged them into my sytsem. I unplugged extra HDDs/drives to be safe, but I played CoD4 w/2x8800gts in SLI on the system ok... BBUUTT.... I want to know thoughts on how it will hold up with a new gtx 260 or ATI 4870 with everything plugged in... will it be ok? Risky? Should I plan to purchase a new PSU, such as an Antec Quattro 1000w PSU for $150 on newegg?

Right, but I also have all the extra HDDs and stuff... I'll check that site, but I feel sometimes those aren't the most accurate? I was also wondering just ppl's opinions if a 550w with my setup + gtx 260 seems a little close for comfort...

It says with EVERYTHING at 100% load, accounting for some USB devices/firewire drawing power, 6 7200rpm HDDs, 4 ram sticks, etc.... all maxed out... 523w, with the gtx260.

I have a 550w 3 rail Antec high quality PSU. Also, I wouldn't have everything at 100% load, of course, and I prob wouldn't have as many extra usb/firewire devices drawing power... soo... to be safe though I maxed it all out, that says 523w... leaving an extra 27w...

so it would prob be safe to use the 550w antec I have, for now?

No power supply calculator is going to be 100% accurate, but that's the best one I've come across. I'm personally a fan of powerful, single +12v rail power supplies, so here are 2 power supplies that I think are worth looking into.

http://www.newegg.com/Product/Prod [...] 6817139006 - Corsair 750watt w/ 60A on the +12v

or...

http://www.newegg.com/Product/Prod [...] 6817703013 - PC Power & Cooling 860watt w/ 64A on the +12v

Hope that helps.

--
br3nd064

550w should be enough for that card.
the cpu will bottleneck the gtx260 a lil bit. oc it!
=]

IMO, 1 powerful rail is better because the multiple rail power supplies waste power in a way. If a multiple rail power supply has 20A on each rail, and your graphics card only requires 18A, then the extra 2 is being wasted and can't go to other components. In a single rail power supply, the graphics card will get the 18amps that it wants, and the 2 amps will not be left over and useless. It will go to the other components.

Also, if you are thinking of buying a GTX 260, a multiple rail power supply with only ~20 amps on each +12v rail will not be able to power it. The multiple rails do not add up. According to Nvidia, the GTX260 requires at least 40A on the +12v rail. Unless you can find an extremely powerful multiple rail power supply, you will not be able to power this card.

The last reason I like single rail power supplies is because you don't have to do any calculating about which rail you use for different components.

If you're also looking to upgrade to a Nehelam chip later on, then yes, the Antec Quattro 1000W would be an excellent choice.

--
br3nd064

You're running a gtx260 with 17A on 2 rails? If that's the case, Nvidia is wrong about the power requirements for the card. Sorry for the incorrect information on needing a single rail power supply. I was going off what Nvidia said the card needed.

--
br3nd064