Best Card for 450W PSU

I am running a 320mb 8800gts (poor timing, bought it just a few weeks before 8800gt came out) on a Corsair VX 450W PSU. It is now time to upgrade for Crysis and GTA 4. Unfortunately the 450W psu puts me just outside the wattage needed to run the higher end cards. I'm also not willing to buy a new psu, I'm just doing a small upgrade to get through the next year or two until its time for a new comp. Other specs: Comp is 1.5 years old, dual core @ 3ghz, 2 optical drives, 1 hard drive, 3gb ram, nothing really special about it.

I don't think my psu is up to the challenge of jumping up to the 4870. The best I have found is the HIS 1gb 48540 IceQ4, now down to $160 with the release of the 4890. Maybe dropping a little more this week; I don't think it can go too much lower, even with the release of the 4770 soon.

So does anyone have opinions on the best cards for a 450W psu? I have a feeling there are a good number of people in a similar position debating whether to get a card now to hold them over, wait till June for all the new cards, or to do a psu upgrade and get a higher end card.

Also what do you think about cards less than 1gb? Personally, I need the 1gb since I already have GTA4, which more or less requires >640mb to play, no matter how fast your card is. Also, after getting burned on the 320mb 8800 (at the time everyone said that more ram is more or less useless performance-wise and that games won't take advantage of it anytime soon) I'm not taking the chance of not being able to play a game because I don't have enough ram on the card.

Both have 2 PCIe connections, the PSU only has a single connector (though it is enough power, even for a 4870).

Read this one two people stating that they are running 4870 on the VX450
http://www.tomshardware.com/forum/ [...] 0vx-gts250