I have 1xSamsung HD160JJ(SataII/7200rpm/8mb). About for 50$ I can get WD Raptor 360GD, but maybe the better choise would be to get second Samsung HD160JJ(for ~80) and put them in Raid 0?
I don't know if 2xSamsung HD160JJ in raid 0 would be spinning faster than 1xRaptor 360GD...?
The problem with Raid 0 is that the data is stripped across the disks, so if one goes then you have lost all of your data, even if the other drive is perfectly fine.
Also know that with Raid 0, unless you're doing HEAVY amount of video editing, or on a regular basis working with huge multi gigabyte files then you're going to see very little improvment in performance.
Really, its not that great of an option. It has its purpose, of course, but when you see those with it in gaming systems, or really those with it in non-video editing (or similair functions) systems then they're wasting money and upping the data loss risk.
No, what I suggest you do is not get the Raid 0 setup or the Raptor. Instead I'd suggest that you buy something like the Hitachi Deskstar T7K250.
The older Raptor is actually kinda slow compared to many drives out their today. It really has not aged well at all, and its low size really holds it back with games and such being so large you'll fill it very fast.
You can pick up the Hitachi T7K250 for around $80, very fast and very nice drive. Also, note in the review how Samsung's HD is consistenly the lowest performer, making it an even worse option for Raid 0.
My HD160JJ in "real world tests" is running really well(in some cases even competing with Raptor740GD). In synthetic tests performance is pure, but I don't care about synthetic tests... http://www.anandtech.com/storage/showdoc.aspx?i=2454
So, what is the main aspect, that you don't recommend me Raid 0?
I personally dont care for Anand, so I'll take their results with a grain of salt.
I dont recommend Raid 0 because it'll offer you not nearly the performance gain you're thinking, and it doubles your risk of data loss. Like I said, if one drive happens to fail then all your data is lost, even if the other drive is fine.
One drive failing resulting in data loss
A power spike or sudden loss can damage the array and cause data loss
Performance delta is small and not worth the added risk
Seriously, just get one of the newer 250 or 300 GB SATA drives with 16MB cache. Hitachi makes among the best and fastest.