an online store selling different blackberry models have blackberry bold 9700 from T mobile USA and another model of 9700 is directly from RIM.what is the difference b/w them..??

You will want to make sure the unbranded version has a working PIN which is able to be registered.

Well. You will want to make sure the PIN is clear on either version actually, regardless.

THANKS for reply but i didnt understand kindly explain more.one which is from T mobile USA is cheaper and the second which as per online store is directly from RIM is higher price.

If the seller is not an authorized retail carrier, you should always verify that the PIN is clear and able to register on your carrier. Sellers who offer used or remanufactured devices might have PINs which are not clear.

You should determine where you want to use the device and what 3G network your carrier is on, as the Tmobile device 3G band is limited ONLY to use on Tmobile.

I don't know which 3G band the unbranded device will have.

hmmm...in my country 3G technology is not launched yet but coming soon as different carriers working on launching.the handset which is directly from RIM is not belonged to any carrier.if i ask you that advice me that which handset i should buy then whats your advice...??

Personally, I would buy the device which my carrier supports. You know that should work and they would be able to assist if you have problems. Buying a BB which they do not carry and support could lead to many more problems.

This article from our FAQ, even though it is about buying a used BB, has some good info and amplifies what JSanders was saying earlier: Buying a BlackBerry off eBay - BlackBerryFAQ

I think the info your trying to find out is that the TMobile one will be locked to TMobile and can only be used with said networks SIM card, unless you pay for it to be unlocked. The other unbranded one more than likely wont be locked and will be able to take any SIM, this is why its more expensive, as you have more options.
As well as that, the TMobile will have nasty branding all over it!

@Matt, the t-mobile 9700 will also ONLY work on T-mobile USa's 3G network. (unless a network supports the frequency t-mobile USA use, which I know of only one: WIND ITALY.)

You mean Wind Canada. Wind Italy uses the same band as all other carriers in Europe, UMTS 2100.

Strange, the thread where I found that out, the carrier was WIND ITALY and the user said they use the 1700/2100 (t-mo USA) not the 1900/2100 that europe use.

OK thanks for that.
So despite the t-mobile us using 2100, they need the 1700 as well?

Yes. The AWS spectrum that T-Mobile USA and Wind CA use for 3G requires both 1700 and 2100 MHz even though they only ever list 1700. 1700 MHz is used for downlink whilst 2100 is used for uplink. In most of the rest of the world, a different section of 2100 (again the only band listed in specs) is used for downlink whilst 1900 is used for the uplink.

Hope that helps...

yes, it does. thanks very much.

You're very welcome.