Seriously??? I know the 290X is a wee bit faster than the 290 (more shaders) but I've over clocked
my 4 x 290's to 1125/1350 and running -t 0,1,2,3,4 -a 1 and only getting 12300 c/m and 46 sh/m.
Is the 290x really THAT much faster or are we seeing a big difference between using clpts on linux
versus windows? If it weren't for the over clocking ease of windows I would definitely be on linux!!

Got Ubuntu installed on my second rig, this time I decided to try out some OC. I used one 290X for this test, clocked at 1150/1400. Only Running -t 0,0, no gains noticed from -a.

[STATS] 2014-Feb-11 19:49:25 | 4582.29 c/m | 17.71 sh/m | VL: 62 (100.00%), RJ: 0 (0.00%), ST: 0 (0.00%)

Wow! That's VERY impressive indeed! I have 4 x MSI R9 290 Gaming cards running
Win8.1x64 with tweaked settings from AfterBurner and I'm only getting ~12300 c/m
with the latest software from NaN. I'm still tackling the 2 thread thing myself and
currently run the -t 0,0,1,1,2,2,3,3 which doesn't get me much more c/m but severely
increases my CPU usage for some reason. I'm assuming you are running Windows as
well since you mentioned "run in their own window" or are you running Linux and just
have multiple terminals open? Much thanks for this info!

:-)

Listen to this. I have 3 280X.

 1 Gigabyte 280X windforce OC
 2 Sapphire 280X regular model.

The -t 0,0,1,1,2,2 -a 1 scrypt did not work well enough for my setup. I reached 8400 CPM with it.
I think I found out why.

 The sapphires run now each in their own window @ 3496 & 3457 CPM each using 2 threads and -a 1 algorith

 The Gigabyte does not like that. It stays around the 1.400 cpm mark. I do use it for the monitor but ok.
 So i delete the -a 1 scrypt; 1600 cpm. MEH
 So I take it back to basics: 1 thread and no algorith choice.
 Now it runs happily at 2.600 cpm.

 ODD

So one 280X is not the other 280X and for PTS mining I would RIGHT NOW recommend the Sapphire regular version of the 280X. BUT just because of my own experience. I like the Gigabytes but I can't find the optimal configuration yet.

 I am happily chugging away at 9700 cpm in total now with these 3 cards
 And @ 1150 shares per hour.

 Not too shabby. With the right cards a full rig of 280Xs (5 pieces) would ramp up to 16.500 cpm and 1.800+ spm.

I can't thank you enough NaN for the incredible miner + revisions!
My current rig has 4 x MSI R9 290, running Windows 8.1 and I'm
currently seeing 11821 c/m (gpu @ 1100 MHz, mem @ 1250 MHz,
power limit @ -15%). All my 290's run at 68C to 71C with fan @ 80%.

Now the above numbers are with just a single GPU thread. When I open
another cmd window and fire up the same exact clpts as the first window
it works, though at a little less than half of the first thread. I'm currently
seeing 10400 c/m in the first thread and 4600 c/m in the second thread.

I decided to kill both threads and start them at the same time and now I
can see that both are running the same c/m which together equal the same
c/m speed as a single thread. I was guessing (hoping) that utilizing the extra
memory on the gpus would help (via more threads) but it doesn't. Just want
to throw that out and ask others to not be too harsh on me... I'm new to this
mining thing :-)

Again NaN, I can't thank you enough!!!