Of course it can hurt, using higher sample rates make the PC work harder to produce the same end result. The harder the PC has to work, the more difficult it can be to work with the project. The cautious approach would be to avoid testing the limits of the machine.

The only time I start projects above 48 now is when I find myself having latency issues.  Otherwise I have not noticed a difference to justify the larger files and processor load.

Yeah but my system should be powerful enough and now that I know about the Read/Write cache settings and other resource saving tricks even ridiculously large projects are fine.
 
The fact X3 is actually pretty darned solid helps a lot too.
 
BUT... now that you mention it I'll keep an eye on such things once I make the conversion so a useful post as always, scook.

Just as a general warning, not all sample rate conversion utilities are created equal. Sonar does quite well compared to many others. We're talking small differences, but since you care enough to go from 48 to 96 it's worth being aware of.

If my PC struggles with 96 KHz, I'll just be mad.

Vab
If my PC struggles with 96 KHz, I'll just be mad.

 I understood so from you earlier post in this thread that you're going to try 96  kHz because you think your audio quality is crap. If I understood correctly, you'll be disappointed big time. If there is something wrong with your audio in a way you can clearly hear, the problem is not the sampling rate. 44,1 kHz is the CD quality, so if your gear and skills are up to the task you'll get good professional recordings with that. 
 
Recording audio the small advantages of 96 kHz can be utilized with top-end mics, top-end treated studios and top-end monitors. If you don't have those, it's a waste of HDD/SSD space and CPU resources.
With soft synths (all plugins don't support it) it can be a little different.
 
Also, many cheaper sound cards, which are advertised to support 96 kHz can only record it with limited features, say, like only one mono track or similar.
 

I am reminded of John T's excellent comment in THE SAMPLE RATE THREAD (God save us all) -
 
"If we want to make good sounding records, we're far better off focussing on rooms, mics, technique, and musicianship (whether technically flash or just instinctively cool-sounding).

In terms of the back end of pres, convertors, summing, and what have you, this stuff even at prosumer level now is way better than it will ever need to be'

And that's what always strikes me most about these arguments. Anyone obsessing over sample rate is looking in pretty much exactly the wrong place."