r9 280x

Ok, 

would this config allow me to use a CX 430M PSU ?

or would i be closing in to the limit of the PSU?

G3258@ 4.5-4.8

MSI R9 280X 3Gb Gaming

Also how long would the card be because i am planning to put this card in an M-ITX case that only has 10" of clearance (SG05BB-LITE) or should i go with a slightly bigger case like the CM elite 110/120/130 ?

430W is not enough for that GPU. You need a good 500-550W PSU to be safe.

It should just fit in the Silverstone, but I believe that case can only use a SFX PSU. I'd go with one of the CM cases, a Corsair 250D, or a Fractal Node case. 

Also, the G3258 isn't a very good PSU. Dual core, not much cache, no HT. It will struggle in more CPU dependent games and bottleneck that GPU. Even with an overclock. Save up for an i5 if you are making a serious gaming rig and if you just want an HTPC then I wouldn't go with the 280X. 

 

well my friend has told me he wants to hell his 280x for $150 ish CAD and its quite a good deal considering its $300+ for a brand new one

and i wanted to keep my PC @ under $400-500ish