DirectX 10 not supported

Minimum requirements state an HD 4870 is the card you need.

The error message given when a too-old or too slow video solution is found is often misleading.  An HD 4870 is a great deal more powerful than any of the HD 2600s, and even the HD 2900 :

http://www.gpureview.com/show_cards.php?card1=522&card2=564

http://www.gpureview.com/show_cards.php?card1=537&card2=564

http://gpuboss.com/gpus/Radeon-HD-4870-vs-Radeon-HD-2600-XT-Mac

(I did note that the HD 4870 is Dx 10.1, a somewhat newer Direct3D API.) 

GPU Boss' database didn't have any Windows 2600s included. 

Gorath, why do you link to GPUboss? It doesn't really contain any useful information when you compare GPUs from different families, nevermind manufacturers. The determining factor in GPU performance is architecture, well any integrated circuit really. A better page to reference might be a benchmark site that can show performance between the selected GPUs.

GPU Review's comparisons across architectures are the ones that are difficult to apply; the SR Labs' results are wrong far too often, and the FutureMark function that once was hosted on YouGamer is gone (Game-o-Meter).  Only GPU Boss and Toms' Hardware consistently attempt to use real world gaming benchmarks.  I consider most benchmarks to have been based on articial testing, and potentially misleading. 

Using Toms Hardware turned out too cumbersome in the long run. 

Well, you could always use their heirarchy chart. All you need something that would gauge relative performance.

That isn't really very specific when it comes to game requirements, but I take your point. 

You could always utilize this website. http://www.notebookcheck.net/ATI-Mobility-Radeon-HD-2600-XT.3770.0.html

Thanks, and I have referred laptop people there, when nothing else was available.  My main interest is attempting to relate a high performance older model GPU to a recent model (probably only medium performance in today's terms), and I have found that the closing couple of sentences in most of Notebook Check's descriptions tend toward an excess of optimism, and I would much rather have a member reply that he was happy with his results in spite of my warning, than vice versa. 

If I accidentally said that a given system should be just fine, and it turns out to be too bad to use in my respondent's opinion, I consider I haven't done him / her any good service. 

Incidentally, I have never used any laptop as a game platform.  I consider them a deadend for that use.  The keyboards are generally awful, and the pointer control pads are horribly imprecise.  When I travelled a great deal, I enjoyed using Notebook size mobile PCs (and always included a small mouse with mine), but I have none today. 

Yep, I understand your reasoning and agree with you. But some of us, including myself simply have to deal with it the best we can. And I have yet to see a great laptop keyboard for gaming purposes.  lol  Thank goodness for gamepad support.

The exorbitant high cost of laptop gaming is self-defeating.  Laptops (and the atrocious Intel video in most of them) are a major cause of developers shunning rthe PC platform in favor of console systems.  A far better option is to use a spoace-conscious base system for gaming at home.  A huge tower is simply no longer needed, if it ever really was. 

A variety of compact form factor enclosures is available that won't overcrowd a college dormitory space, or small apartment, what have you.  Continue to avoid "skinny" PC cases, which do not cool well and require Low Height GPUs that tend not to include game capable cores in them, but the variety of small cases is both excellent and cost conscious for the budget.

Once you actually have a base PC, just keep a skinny, small, and light weight notebook system for portable convenience until it actually wears out.  Over eight years, for only $200 USD every couple of years, update the base machine to a useful standard for games, and you don't have to go through three complete laptops in the same time frame!