its the R2 and i was gonna buy one 6990 cause i cant aford to do 2 right now being it will cost 800 bucks at best but i see that the HD 6870 i can buy for 150 to 200 each so if i went that rout would it preform better than a single 6990

I had a friend at notebook review willing to sell me one for $320, but only around the US! :D

I don't know about HD6870m CrossFire, but I heard HD6870m's performance is roughly the same as HD5870m.

Assuming a HD6870m CrossFire perform roughly equal to HD5870m CrossFire, the performance should be equal (faster in some area, and slower in some other) than a HD6990m.

3DMark 06 Score:
HD5870m CrossFire = 16,596
HD6990m = 21,305 (this score is a bit weird, since I can't hit 20k with mine)

3DMark Vantage Score:
HD5870m CrossFire = 14,096
Single HD6990m = 13,341

Crysis GPU Benchmark:
HD5870m CrossFire = 29.7fps on Ultra settings
HD6990m = 30.7fps on Ultra settings

Source: HD5870m CrossFire & HD6990m

ok well if thats true then i might as well go with the single 6990 so i can add another down the road my next question is this will my power supply be enough for the 6990i currently have 2 4870's

I'm sure dual HD4870m consume more power than a single HD6990m...

The question that persists is, whether your power supply able to feed dual HD6990m or not... That, is the real question xD

haha well i all need to wory about is one for now can you buy bigger poer supply's for these laptops

I don't think you can change the power supply of laptop, not sure though...

Yeah, you can get bigger PSU for laptops, you need to have 240W to run 6990 in crossfire.

Easiest way to find out is for you to look at the label on your PSU. What's the wattage rating?

M18x with dual GPUs ship with 330W PSUs. You'd not need that for a single GPU as Krish writes

krishnooof said: Yeah, you can get bigger PSU for laptops, you need to have 240W to run 6990 in crossfire.

Wow I didn't know that, nice info though

and, 240w to run 6990m in crossfire? That's small... lol. Used to run 1250w PSU on my desktop PC >.>

krishnooof said: Yeah, you can get bigger PSU for laptops, you need to have 240W to run 6990 in crossfire.

I wouldn't have thought that was enough, but perhaps since it's for the M17x. I've seen other users out there say they are using 240W though

http://www.tomshardware.com/reviews/gtx-580m-sli-hd-6990m-crossfire,3022-11.html

my power suply says input:100-240v is that right ?

gumption37 said: my power suply says input:100-240v is that right ?

well, that means that you can plug it into wall socket with 100-240v, so same PSU can be used in europe and usa. Look at the model, there should be a number in it suggesting your PSU power

modle is GA240PE1-00

so is that a 240 then cause it has 240 in it ?

yep, it's a 240W psu