A lot of the new hard drives use USB3 and that is pretty fast. Additionally internal drives use the newer SATA interfaces. My computer came with a 1 terabyte hard drive 4 years ago, and now have about 136 gig stored on it. Pretty decent 1 terabyte and more can frequently be purchased for near $100. That is dirt cheap compared to what they cost a few years ago. I back up to a 1.5 terabyte external drive and also do instantaneous back up with my 1 terabyte HP drive. This has a back up program that backs up every 5 minutes whenever the computer is on, so effectively I have a full back up copy of my computer that is no more than 5 minutes old. Many Many years ago, I had a hard drive go back without a back up, and it was a very painful experience. Since Flash drives are so inexpensive today, it is good to have your photos and music backed up to one of those. You can never have too many backup copies. If you ever suffered a complete loss, you would understand that. The fact that you have a large main drive is not problem since you can also get a large back up drive and if you have a USB3 drive, it s pretty quick. The reason the turn out so many computers with 1 terabyte and larger is that the cost of a hard drive that large is reasonable and people like having large drives so that they almost never run out. You can also move infrequently accessed data to an external drive to gain more room for more frequently accessed data. This is a pretty good decade for not losing computer data.

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