Looking to add SSD to XPS 8100 desktop

Hi

I have an old (in computer terms!) XPS 8100 that actually suits me pretty well apart from the hard drive - it's very slow and after booting up, I sometimes have to wait up to 20 minutes before it calms down and stops churning. There are actually 2 x 1TB drives on there, but it's the Windows disk that is the churner...

What I want to do is add an SSD which will act as the boot drive and have Windows installed - I can then keep the 2 original 1TB drives and just use them for storage.

My question is whether the motherboard in the XPS 8100 can support an additional SSD as well as the 2 original drives? And if so, would a drive such as the Samsung EVO 870 be OK? 

I believe the motherboard will probably only support SATA 2 rather than the newer SATA 3, but it will still provide a much needed performance boost over the old drives.

Thanks