Xeon processors include extra circuits for data exchange between processors in case motherboard contains 2 or more processors. Xeon also comes with wider variety of cache sizes. Otherwise I7 and Xeon based on the same architecture are the same.
As far as "what they run at when there are 2", that's a mobo issue.... not much you could do about that. There is no practical nor perceptible difference at all. PCIE runs at 500MB/s, max., PER LANE. (x1 has 1 lane, x16 has 16) 500 MB/s is waaaayyyyy more than is ever called for in a trading setup. (Some guys still running a 1 or even 2 Matrox PCI quads... and that's 100-133 MB/s.. SHARED by all PCI devices.)
Thanks for the detailed explanation; this means that even the 'slow' x1 PCI-Ex videocard will be usually faster than a fast old-stile PCI card?
One of the best traders I know, trades off a netbook plugged into a monitor. He uses Xtrader(TT). He says he has never had an issue. If all you run on the computer is your trading software and nothing else, you won't need a big rig. Throw your charts on another computer.
A powerful superfast computer does not make one into a profitable trader, but they are nice. It's like driving a BMW into a Walmart as opposed to a Saturn. Either one gets the job done, but what would you rather be driving?
Thats actually a very interesting idea. Seprate charts and trading platform on two different computers. Nowadays, 2 laptops will costs less then $1000
Xeons are for number crunching - servers etc. i7 is really the same processor, speed wize, for the desktop version. Trading you really do not need the number crunching as your data is mostly streaming from your platform providers.
Yeah, basically Xeons are special versions of the same CPU. They allow dual/quad-CPU configuration on the motherboard for really demanding CPU-intensive tasks. Not really something you need for a trading system. So effectively, there's no difference on a single-CPU computer. On the other hand, I have datacentre machines with quad-quad-core CPUs running 40-50 servers. Probably the ones sending you your datafeeds...
http://www.tradingcomputers.com http://www.elnexus.com/articles/Nehalem-2P-Benchmarks.aspx http://www.tomshardware.co.uk/phenom-ii-940,review-31485-21.html