Good Luck on a custom box. Hope this gets to you in time. My last attempt at building a system was interesting and expensive. That cptr is now just a backup and only lasted about 1-2 years. After my more recent purchase of a Dell workstation 670 from the outlet I evaluated the cost, speed and components. The Dell ( and probably others like HP workstations) are ready to rock. Just check the benchmark on my "out of the box" purchase. 287 seconds for the run. Best at the time ... and probably still best. I see Dell has a 690 workstation now that features room for growth in that it includes dual PCI-E slots for graphics cards and RAM up to 64gb. I buy into the FX540 and Fire video cards for low end cost and use... But I am runnning dual monitors with revit at 21" vertical and 30" horizontal with dual screen activated. They run dual DVI at 1600x1200 and 2560x1600. Try to obtain that from the lower end cards. Choose your system and cards based on what the guru's are saying and consider where you are going. If you are building for the future dual pci-e is important when using dual monitors. Revit may not currently benefit.. but may some day. Also, rendering is important to me so the dual and quad core processors are awesome. I chose dual xeon dual cores in the dell box. A great match for revit and for rendering in revit. My files for residential are from 28mb to 60mb+. my template is 8mb alone. Opening a project takes a minute. Rebooting the cptr takes less than a minute. And the dual view monitors work great... allowing me to keep open 4 elevations in wireframe and work on three views and a 3d view on the 30" monitor. Note: I purchased the Quadro FX4400 for less than $500 on ebay. There are even better deals if you can wait to upgrade your cards... the 4400 really only helped the use of dual monitors and the quality of 1600x1200 for them. When I benchmarked with the 270 model card that came with the cptr I reached #1 best benchmark.. after replacing it with the 4400 there was no change in benchmark speed.Most notably, and as referenced all over the Forum.... Dual Core and Quad core processors rule. Some notes are out there about the extreme core duo compared to dual and quad cores. I found the 2x dual cores effective.... so much so that I would move toward 2x quad cores if budget allowed. I would not go the route of boxes that were lighter than a workstation.... workstation pricing... is very good.on hard drives, I run a 15k SCSI for main processing files and OS with a 10k SATA for storage of files not often used. I believe there is a benefit here but have no facts other than comparing to my old custom box which did not measure up and did result in the 20 minute file openings and freezing occurrences.With the Dell Workstation .... RAM additions will be available throughout your years of growth in Revit. I currently run 4gb on WinXP Pro. when I monitor the processes... Revit runs as noted by others.... about 20x the file size... so for me 2gb for Revit and 1gb for windows and other open programs is correct. I see room for growth as my file sizes increase by adding ram to 16gb as necessary. The Dell 690 has room to 64gb. Of course... all the RAM is relative to your OS. a 64 bit OS will be necessary and is reasonable for projected future needs... but currently a bit of an issue today. Costs are important, I could not have achieved the combination of compliments in the Dell Workstation by building them into a custom box without spending $5-6k. Dell outlet offers workstations starting around $600. My system came ready with 2x dual core xeon 2.8 processors and 2gb ram and large high end scsi and sata drives at a reasonble price... about $3100. If I look at my purchase in hindsight... I bought a computer that will live with Revit for about the next 7 years. My custom box lasted 2 years at best. The old saying is ..." you can pay now or you'll pay later."Lastly, the Dell box has much directed cooling that really helps. it comes with a 750 watt power supply and the box runs quietly and maintains proper cooling. That is much different than my custom built box which was noisy and ran hot.

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