Help with hardware choosing

GregaG

I read on forum a lot and i just cant make my mind i have 1000â‚¬ limit that i am willing to invest based on how profitable (future prices and difficulty) i might invest more.

I would like to buy at the site i am linking, because its cheaper then local stores and i know i wont have problems with supply time (its 3 days after i wire the money).
Well supply time is what mathers for me the most , but i do understand that limits me at hardware choice and prices.
I have some questions before asking hardware thought.

Which windows is better to use, will there be an significant difference between win7 or winxp (maybe quality of drivers)? I am also open to linux if results are any better on it.

To get Pci-e raisers it will take time, i will modify them once i get them by soldering 12v supply from molex connector. The question is is it possible to stick GPU in motherboard without fixing it to anything and its gonna be fine or the vibrations from cooling might cause problems ?
i do understand the danger of frying hardware if i in any kind i bump or shake it even in slightest manner, but the rig will be left in a closed room and before doing anything on it i will turn it down.

Also i see some people using 4Gb ram and even recommending to people already mining to upgrade from 2Gb, ram doesnt affect mining right ?

I am not used to these power consuming high performance graphic cards as i am not so demanding user. But i noticed some of graphic cards come with 2 6 pin connectors at the top, do both of connector have to be plugged to get the full potential out of graphic card or is 1 enought? Asking to know which PSU to choose.

Ok first dilemma is of course which graphic card to chose
[url=http://www.mylemon.at/kategorie/computer-hardware/grafik-und-videokarten/grafikkarten.html?filter=5]http://www.mylemon.at/kategorie/computer-hardware/grafik-und-videokarten/grafikkarten.html?filter=5[/url]|177&order=4
i was looking at
Sapphire TOXIC R9 280X for 284â‚¬ and if i am not mistaken i should get out of it atleast 580 kH/s
Sapphire RADEON HD 7970 OC for 337â‚¬ should get 700kH/s
Power consumption looks kinda the same 7970 has around 30-50W more.
i have been looking at [url=https://litecoin.info/Mining_hardware_comparison]https://litecoin.info/Mining_hardware_comparison[/url] for comparison.

Now for mining rig i cant really decide if i should made something standart size or something with itx.
Why itx you may ask?
The price of 2 itx mining rigs will be prety much same as 1 standard mining rig. while i will save at motherboard/cpu and PSU prices, i will need two times more components.

Benefits?

If 1 mining rig dies other 1 still works. Easier to fix as i can test parts on working mining rig (well ok not really benefit, i can do that on my computer).

Once mining is not profitable or mining rig is just out-dated i can always use itx mother board for nas server in this case i would have 2 identical and i would keep 1 for fast fixing of nas server. I would just transfer 2 Gbs of ram from second machine to first in that case. I end with 2 disk for backup and 2 PSU (always need those as electrician).
So i can reuse everything except for graphic cards, which would be sold in that case.

I also lose the need for 1kW or 1,2kW which are very expensive and can go for a 600+W.

I have 2 concerns with itx. Mobo might fry as low cost mobo with E240 or E350 werent meant for high end GPUs, but it has Pci-e so it should uphold to power ratings right?
And poor bios, could it be bottleneck for mining capability?

Anyway Itx hardware:
Motherboards
[url=http://www.mylemon.at/artikel/asrock/e35lm1/asro-e35lm1-amd-a50m-gvsm.html]http://www.mylemon.at/artikel/asrock/e35lm1/asro-e35lm1-amd-a50m-gvsm.html[/url]
[url=http://www.mylemon.at/artikel/asrock/e350m1/mbmitx-amd-a50m-e350m1-inkl.html]http://www.mylemon.at/artikel/asrock/e350m1/mbmitx-amd-a50m-e350m1-inkl.html[/url]

620W Seasonic PSU
[url=http://www.mylemon.at/artikel/seasonic/s12ii_620/s12ii-620-620w-atx22.html]http://www.mylemon.at/artikel/seasonic/s12ii_620/s12ii-620-620w-atx22.html[/url]

Mushkin 2GB DDR3, 1333 MHz ram
[url=http://www.mylemon.at/artikel/mushkin/991768/d3-2gb-1333-999-silverline.html]http://www.mylemon.at/artikel/mushkin/991768/d3-2gb-1333-999-silverline.html[/url]

disk would eighter take cheapest 32Gb sandisk or 160Gb 3,5"

And if my idea with itx is not viable then:
Motherboard
[url=http://www.mylemon.at/artikel/asrock/90_mxgip0_a0uayz/mbam3-amd-970-970-extreme4.html]http://www.mylemon.at/artikel/asrock/90_mxgip0_a0uayz/mbam3-amd-970-970-extreme4.html[/url]
[url=http://www.mylemon.at/artikel/gigabyte/ga_990fxa_ud3/990fxa-ud3-socketam3-ht3-0.html]http://www.mylemon.at/artikel/gigabyte/ga_990fxa_ud3/990fxa-ud3-socketam3-ht3-0.html[/url]

CPU
[url=http://www.mylemon.at/artikel/amd/sdx145hbgmbox/cpu-am3-sempron-145-1mb.html]http://www.mylemon.at/artikel/amd/sdx145hbgmbox/cpu-am3-sempron-145-1mb.html[/url]

PSU
[url=http://www.mylemon.at/artikel/seasonic/x_1050/netzteil-1050w-x-1050-gold.html]http://www.mylemon.at/artikel/seasonic/x_1050/netzteil-1050w-x-1050-gold.html[/url]
Would 1050W be enought in this case?

Ram and disk stay the same as with itx.

Any thoughts and suggestions are welcomed.
And yes maybe i am a bit crazy when it comes to itx and embedded hardware :P