Ah, well, not that puts everything in perspective
You mention 'business' and most us thought this was more of a 'small ball' problem. Seriously though, if you don't have an SSD and can afford one, you'll be blown away
"Small ball?" Don't know what you mean. On the SSD -- know that -- been there -- done that.
But it's "bidnis." SKYPE can't get better. Excel can't get better . . . nor none of the rest . . .
For me, the point was that I'd done my rental property work on my "flagship" system, and didn't waste time allocating hours spent in "bidnis" v "Personal." It wasn't feasible to make the computer tax-deductible. Then, they elected me to the condominium board as Treasurer -- 3,000 miles away. Needed SKYPE, but could've had it on the flagship. But the separate accounting, e-mail, etc. added to the income-earning aspect of my property-management makes it justifiable. Since it's an old computer, my guess is that it's depreciable value might be found to be $200 by a documented market search, but anything beyond would be pushing it.
For the OP, whatever tax-regime he's under or whether he's selling mom's tamales on the corner or boot-strapping a new Latvian startup, he may use the computer differently in a couple years. Maybe he's not even assessing his "tax-regime" environment, and he wasn't clear as to what "bidnis" he meant.
But suppose you had to justify a computer purchase for any number of "bidnis" activities. Only the IT guys would wonder why you needed a quad-core. In accounting, it's . . . . just . . . an extra . . . Fifty Bucks.