My office software having weird issue

[jimmyrules712]

I've got a nissue Id like some opinions on. At my office, we use some special database software to manage our 20,000+ members. It is hosted on our server, but any PC in the office can access it. (I have to installed a small client program on each PC first). Well this program tends to run a bit on the slow side, probably because it's such a huge database, but I do know it runs much faster on our newer machines (P4 2.8ghz with 512 DDR) compared to our older (P3 500mhz with 512 Sdram).

Heres the issue. We upgraded a few computers so now I have a couple systems that I can use to replace the P3 500mhz systems. The newer ones are P4 1.6 ghz with 512 DDR. However, after doing a fresh install of windows on those newer systems, and installing only our database software, they run it even slower then the 500mhz systems do. I've been baffled by this, can anyone think of a reason why this might be happening?

[EzyStvy]

Did the old machines have a lighter/faster OS like Win98 and the new machines have XP?

Do the newer machines have all the windows updates?