Confuse again with too many models...

before i start, let me give you my pc specs:

Asus A8V Deluxe Motherboard (S939)
AMD Athlon 64 3800+ (2.4ghz Stock - OC@ 2.7Ghz)
3gb DDR 400 Dual Channel
2x WD 160gb SATA 150 Raid 0 Mode - WD 250Gb SATA 150 (Backup)
Thermaltake TWV 500W ATX 12V 2.2 Power Supply
LG 19" LCD Monitor

Now.. i had an Evga 7800GS OC AGP8x 256mb DDR3 256bits clocked @ 430Mhz Core and 1300Mhz memory. i overclocked @ 475Mhz Core and 1380Mhz Memory without any problems. My game that i used for my benchmark is F.E.A.R
I had around 138fps for the maximum frame rate and 35fps for the minimum @ 1024x768 with everything max out.

Not long ago, i bought the ATI Powercolor X1950PRO 512mb DDR3 256bits clocked @ 575Mhz Core and 1380Mhz Memory. i overclocked @ 621Mhz Core and 1575Mhz Memory without any problems.
in F.E.A.R, I had 202fps for the maximum and 61fps for the minimum @ 1024x768 with everything max out. That's was cool but my ATI card's keep crashing in windows. In games, no problems, can game like 4 hours and never crashed but in windows, anything i can do, it just freeze or crash and restart the computer. (It was worst when i had catalyst installed)

So now i send my ATI back on RMA but can't have those no more where i shop for my stuff. Powercolor don't seem to have a RMA service on there web site. So i have to upgrade to PCI-Express. Just need to change my board from ASUS A8V Deluxe to A8V-E Deluxe wich i have where i work (computer store).
So my question is this:
Wich one is better between those cards:

MSI NX8600GTS-T2D256E OC 256MB DDR3 (128bits) 700Mhz Core / 2100Mhz Memory
ASUS EAX1950PRO CROSSFIRE 256MB DDR3 (256bits) 581Mhz Core / 1400Mhz Memory

Now i tought that DDR3 was always 256bits but it's look like in the 8600 model, there only 128bits but clocking is alot more than the ATI who's at 256bits. is the memory interface more important than clocking???

I don't wanna loose power in my games that i already have but games like S.T.A.L.K.E.R or Dark Messiah of Might and Magic demand a bit more than what my Evga 7800GS AGP8x can give.

So wich one should i buy??

Sorry for the bad writing

Thanks for all your comments.

For now, no because my motherboard's not Crossfire ready... but when i'll upgrade, it will be SLI or Crossfire ready and i'll choose the card a that time...

So you think that the 1950Pro will beat the 8600... good cause it's cheaper hehe Thanks for your reply. ill go with the ATI.

actually, i tried all drivers from ati, from 6.8 to 7.6 and even the one from powercolor 7.2 and the one on cd was 7.1
i used driver cleaner to remove my drivers.
My PSU have over 38A on the +12V ... i think it's enough ??
Cause... when i put back my Evga 7800GS, where it was freezing with the ATI, it doesn't do it with the Nvidia.
it's been around 12 hours that my NVidia's back in my pc and no freeze at all.
With the other one, about 10min in windows and it freeze. I got all my driver up to date, even did a Bios Update on my motherboard but it changed nothing. And i don't wanna do a bios update on my ATI Card cause it'll void the warranty.
Thank for your reply I'll go with the ATI 1950 Pro.

You didn't mention that you did ALL THAT and that you had a decent PSU, so yeah the card was probably faulty. And good choice on the X1950Pro.

All 1950Pro cards are crossfire. It's built into the card as standard same as HD2xxx.

Cool - I didn't know that. I was wondering why the card I bought didn't have the connector but that explains it.

You can run ATi cards in Crossfire mode in an SLi MoBo, but not easily, and really if you don't already know how, then I wouldn't recommend it, I'd simpply suggest getting a better single card.

IMO don't worry about Xfire or SLi, when you're ready to upgrade, sell your old card and buy a new better single one.

Probably by the time you consider an upgrade there'll be a GF8800GS or HD2900Pro style card that would likely still beat 2 X1950Pro in Xfire. I see no need to worry about a multi-card future with the X1K and GF7 generation at this point.