Upgrade Choices - 670 SLI or R9 290 - Help me decide.

Currently I've got a single 670, and a couple of hundred quid burning a hole in my pocket. I'm tempted to grab a second 670 and SLI it at the price scan have it on today only (£161) but I'd need a new PSU also (I currently only have 2 PCI-E connectors) so total cost would be around £240, less what I could get back for my current PSU (maybe £40). So total cost say £180.

That then set me to thinking - would I be better waiting for the aftermarket cooled 290s. Overall cost is likely to be similar say £320 for a card, and maybe £140 back for my 670 after paypal fees etc, I'd imagine performance is going to be slightly lower, but theres obviously less hassle with drivers etc.

I'm having trouble locating any comparisons though.

You could just about get away with an extra 670 on that PSU in my opinion. You got any way of telling us what your current power draw is (wattemeter?).

Butuz

I reckon it would be pushing it a bit - according to my whole house monitor thingy it looks to draw somewhere in the region of 400W at the wall at the moment, which would mean about 320 DC watts (assuming 80% efficiency) I'd be banking on the other 670 not pulling more than 200W, since its a 170W TDP it would be cutting it finer than I'd like, and certainly doesn't leave any OC headroom.

ok but bear in mind the british gas type monitors are not accurate at all (unless you call +-100w accurate!) - a maplin wallplug wattmeter is orders of magnitude more accurate.

Mine says my 1 x 3770k & 2 x 7970 pulls about 550AC watts out of my 850w platinum. That's why I think you'll be OK - I'm running approx. 2x R290s worth @ 550w. 2x670 is much less power hungry.

Also as a parting shot - I've got loads of BeQuiet PSu's in the field - they're GOOD. I've pulled 650wAC constant 24/7 out of 600w gold versions - they're a bucket load more hardy than the usual coarsair/xfx/generic whatever PSUs.

Butuz

You could use a 690 for benchmark reference, almost same performance as 670 sli.

My opinion is 2GB of vram is getting old now. 670 SLI has the power but sadly nvidia are often a bit low on RAM.

I'd go with a 290 if the after market coolers do a good job.

I would go with the 290, 2 cards are still a gamble and if you have heard the true audio demos it may help you lean towards AMD, also at risk to contradicting what I just said, it seems that mantle enabled games will see CFX as 2 cards so will scale very well and more than likely eliminate any type of micro stutter!

I have also read that a small percentage of cards can be unlocked to 290x shader count although the risk only comes with a 2FPS reward in Unigine Valley....

Go with the R9 290, but wait for a better cooler.