If you intend to game on it then neither of the AMD drivers is up to scratch. You'll get around 50% of the potential performance.
Nvidia's Linux drivers are about on a par with the Windows ones.
So if you're committed to using open source drivers then go AMD and take a (big) performance hit. If you just want the best performance per £ then go Nvidia.
Current decent cards (in terms of value) are the GTX 970 and 980. If they're too expensive then (in descending order of goodness) 780, 770, 680, 960. The 'ti' cards are always better than non-ti (but also more expensive) and often better than the next non-ti card up. And more VRAM is better (up to 4gb, any more than that is wasted unless you play at 4k).
OK, I'm liking that. New 560 Ti's are hella expensive here. I'm definitely open to Nvidia, but my past shopping experiences have tended to affirm that Radeon generally gets more bang for your buck.
I'm actually needing a new pc /DIY build, and I'm not going to be able to recycle the agp 4650, so I've got to get the components down below a MrsD.-goes-ballistic scenario.
Edit: oh yeah, and we're getting killed on the US$ exchange.
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"Giant pig hot air balloon crashes after tangling with a cowboy-shaped one"
My two most recent graphics cards have been Radeons. I've owned more Nvidia cards over the years though, 4 I think, including one I bought for my HTPC which has been replaced by my Pi.
So I chickened out on the $.5K new pc ask, and decided to give my aging creaky old system another kick at the can with a new psu and hdd.
Been having intermittent problems with the drive for literally months, and the latest dvd fail (whatever the underlying cause) seems to have pushed it over the edge into a somewhat precipitous decline.
It was still bootable into linux last night, but slow and apt to lock up -- symptoms that have occurred often enough to suspect the issue is mb / psu related. xp hasn't been usable since the last optical drive fail, and for that matter its partition hasn't passed a chkdsk in recovery console even though all other ntfs volumes came up clean. The disk ominously fails all SMART tests** run from linux (smart data shows the drive as ok). FWIW, it's not made any clicking sounds so far.
If it turns out there's been mb damage then I can at least make use of the new components. I'm going up a grade from the usual dirt-cheap, minimally adequate psu to this, which could actually work with a more power-sucking gpu should it come to that and, who knows, may even 'fix' some of the issues with current system.
**Edit: And it just passed a SMART test. Go figger. (still gonna replace it, bought the new drive already)
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"Giant pig hot air balloon crashes after tangling with a cowboy-shaped one"
The beast is in. It is huge and I honestly didn't think it would fit, but it did (NJ). The ginormous cooling fan is really quiet. The PATA dvd burner and floppy drives appear to be working (before, using either made it freeze up). Next step is to connect the old hdd drive and see if that boots. If it does, see if xp works any better (but I think it's damaged), asuming it doesn't, or work well enough, essay a repair install (so I don't have to reinstall drivers & apps). If that fails, reformat the partition and clean install.
I'd never even heard of this, but apparently after formatting a new sata hdd from xp, you need to run an alignment utility (wich explains why I always get 'partition doesn't align with cylinders' reports in fdisk -l).
The utility probably won't work too well on my existing layout (numerous ntfs & ext4 partitions, though the table was made in xp) and there's a risk nuking the data on it, so I won't try it there.
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"Giant pig hot air balloon crashes after tangling with a cowboy-shaped one"
Bloody hell, drive alignment, I remember having to do that years ago with a large drive and XP. It really was years ago, because that's how old XP is!!! Stop using it.
bastard by name