As others have said, your computer seems like it should handle the recording process. And, with some of the help you've already received, it looks like you might be on the road to getting this figured out. But, there are some simple maintenance things you should consider, also.
Because most audio files are so large, you need sufficient disk space to work. How much is debatable, but if you are limited to less than 1 third of your drive space, you might need to upgrade. And if you are limited in space, those audio files are opened where ever Windows can find space so it could be those files are spread all over your drive, in any available space it can find. If you haven't defragmented your drives, you should do so on a regular schedule. Keeping any free drive space as contiguous as possible would be a big plus.
Also, Windows takes up quiet a bit of available resources and many DAWs also have so many whistles and bells that they use up a lot just opening. I don't know about Sonar, so it might be small enough not to be a problem in that way. And adjusting the size of your Windows swap file could be beneficial or maybe the drive for where the primary is opened, secondary, etc. Some people say to let Windows decide that, but you can sometimes read up on swap files and be able to tweak yours. A large setting can be beneficial, but sometimes too large can be more harm than benefit. Whatever you do with the swap file, remember what it was set at before you start messing with it, so you can put it back to the Windows set, if you want.
Also, depending on your interface, the driver for that hardware might not be stable. You might want to check for any updates to it, and even check their web site for any possible glitches in one driver or the next. Usually, if you have the lastest driver for something, it's the best one. But sometimes, there are small updates that fix unforeseen problems. And there can also be software that isn't working together, like you'd hope. Loading a lot of VSTs, be them VSTi or effects can also drain your resources down pretty quickly.
Any time you are searching for the solution to a computer problem, it's best to keep track of what you've changed, and don't change too many things at once. If you change too much at once and something goes wrong, you don't know which thing you changed was the cause or if it was a combination of things. Go slow with any changes and keep track of what your doing. Also, do backups before you make any major changes that you can't revert from. Things like this can keep you awake at night.
While your issues might be DAW related, it's always good to keep up with necessary maintenance on your computer, so you can hopefully cancel that out as part of your problem.
thanks again everyone.
