If you want something fun yet still very powerful and affordable, you might consider a dual socket HP z820 workstation. This was HP's high end business offering back in 2012-2013 and with the right chips (which are relatively cheap on ebay at this point) they are still a force to be reckoned with.
This machine does not have much in the way of competition. Even now, most state of the art rigs dont even come close to matching it in memory bandwidth...or CPU power for that matter. Obviously it needs to have both sockets populated to achieve this.
In order to
It was pretty much the cream of the crop for a number of years when it first hit the market. Dell has their own workstation equivalent, but is nowhere near as aesthetically pleasing on the eyes as the 820. In fact, I don't like the dell styling at all.
The computer is innovative and even groundbreaking in a number of respects. First of all, it's a 100% tool free design. Meaning everything locks or snaps into place and you can essentially disassemble the entire rig without the use of a Philips head screwdriver, or any other tool for that matter. This makes upgrading hardware, or troubleshooting a problem a real breeze. For example. It literally takes about one second to remove the CPU cooler hood that sits atop the sockets. And don't think for one second that HP was cutting corners by having "snap on" components. No, this is very high level stuff operating at a very high level of performance.
Speaking of air flow, the z820 also has one of the best cooling systems ever put to use in a workstation computer and includes active cooling on all 16 ram slots plus a high quality 80mm PWM fan above each CPU. As you probably know, many servers in the wild use segregated channels to route fresh air through specific "corridors" within the chassis...and the cooling potential is very good so long as you can keep a steady rate of fresh air coming in. It's more or less the same in the z820, only it's much more quiet than a server. And in point of fact, quieter than most desktops as well...
z820 CPU channel and hood:
In addition to that, and to give you a complete understanding of the level of performance of this cooler, you can completely lose a 80mm fan (and I'm talking about the fans that sit directly above the CPUs here) and you can still use the machine aggressively. For example, my testing revealed that after multiple CB 15/20 runs, the chip with no active cooling amazingly holds at about 165*F. Still well below the 212*F ceiling. How can this be possible, you might be asking yourself...? And it's simple. The CPUs and their associated heatsinks sit directly in the path of an airflow channel;. Starts in the 5.25" drive bay area by pulling fresh air through the front bezel, then the air flows over both CPU coolers (which are offset) and subsequently exhausts via the two 80 mm PWM fans at the back of the case, In other words, HP has built redundancy into an already exceptionally high performance, balanced cooling solution.
This is not something you see every day. So you have near perfect airflow in this case, which is another thing to add to the pros list. One other thing. it has a 1125w (up to 1250w) PSU, and lots of PCIe expansion shots to allow for upgrades and modifications down the road. Had no problem putting my massive 5700 XT in there, with room to spare.
And you wouldn't know by using it that the case actually contains six 80 mm fans. To give you an example of the supreme operational quietness of the z820, I can run CB extreme or CB R20 and in many cases the fans dont even move from idle. It's pretty crazy.
I've never seen anything like that, ever. In fact the most I've seen out of the fans is about 20%, and even then the fan noise is still pretty faint. You also have options in the BIOS to ramp up your fans a little quicker if you are really hammering it.
Leading to the radiators. Yes the machine had a factory watercooling option, which makes it a very unique kind of machine with a significant place in the histories of technology. Plus the rig caught my eye with it's beautiful brushed aluminum finish and I immediately knew I had to get one and put in my computer collection. So I bought two of them! lol
Surprisingly, these little 80 mm coolers have huge capacity for heat dissipation. Even with the power hungry Xeon 150w E5 2687w ( Intel's fastest 8 core Ivy bridge) you still cant hit the ceiling. Very robust, to say the least. That's essentially 300 watts of heat being dissipated by a mere 160 mm worth of radiator. See for yourself:
I will be back later to fill you in on my CPU recommendations.
Hint:
OEM Ivy Bridge > RETAIL Ivy Bridge
I am running the E5 2673 v
2696 v2
But short answer to your question? No, cant do much in the way of overclocking on these Xeons as already mentioned (at least on a z820. Although, if we pool our money together I'm sure we could have someone over at bios-mods.com help us out with custom BIOS or something like that. Seeing how CPU cooler itself is almost perfectly designed for pretty serious overclocking, that would be a thrilling upgrade.
Due to the fact you have limited headroom to OC, it's important to select CPUs that will compensate for that lost potential. What I mean is you want to get a CPU with a relatively high turbo or base clock for optimal results. You probably already know this, but I just wanted to put it out there.
Okay, I will take off my sell-you-a-z820 hat now
