Looking at an older HP server Wondering if it will be enough for my workload

Okay, so I am looking at possibly picking up an older HP server from savemyserver.com and just want to make sure it will work well for what I want, which will be basicly hosting VM,s VIA proxmox. Right now i'm just using my old gaming machine a i7 [email protected] 2.66Ghz, 16gb ram and a 1tb WD Red. This works okay, but has really bad I/O delay when getting more then one or two vms running, and even worse if they are windows vms sometimes its upwards of 30% drive I/O delay, also it's not enough ram.

Current Projected Usage:

Several Linux VM's running minecraft server, teamspeak, NAS backup and testing new distros.
Setting up a Windows Server 2012 Domain with Active Directory, DHCP, DNS and other stuff for learning/testing. Possibly server clustering.
Several Windows OS's to be used in the testing/learning Domain.

The server i am looking at would be specced as so:

CPU: 2x 2.9Ghz xeon quadcore no HT
Ram: 24GB ECC maybe 32GB DDR2 
HDD: 8 300GB 10k sata probably going to be in raid 5 using 7 drives with one hot spare.

What I am wondering is will this substantially improve the performance of the VMs?

Would 15k sas drives be noticeable better? Or would the 10k sata drives be fine?

The CPU i have currently is not a problem has plenty of usage to spare so I think I would be okay with the same amount of cores plus they would be all physical instad of 4 logical.

I would consider using BTRFS instead of RAIDing them together.

In terms of improving performance of VMs over what you currently have: Yes. The only issue I see, is that it's and old Xeon, but it should still pack a bit of a punch. The higher volume of memory will help quite a bit in VM performance.

As for the Drives, 8, 10k Drives will blow away the WD Red. I would make sure the RAID controller in the system is operating properly, and that the battery (if it has one) is functional.

As for a noticeable difference with 15k SAS drives: it really depends on how many VMs you are running, and how much they access the local storage.

The RAID card should come fully functional with its battery, the unit would have a 2 year warranty so if nothing works I'll be requesting a new one.

I was also looking at a newer HP G6 but it ended up at $1k which is just too much for me, which is why I chose the older Xeon in the HP G5 scheme.

How does BTRFS work with a RAID card? Is it just not used for RAID and acts rather as a drive controller?

To setup the RAID system, you set up all your drives as JBOD, and let BTRFS sort everything out.

@wendell can correct me if I'm wrong on that.

As for it being old tech, tried and true! I meant you shouldn't expect top performance from new software that is optimized for newer CPUs.

i agree that those 8 10k drives are going to dominate that WD Red.

do you know the model of that Xeon?
if its the Nehalem that thing is rock solid. (in my opinion)

Server has already been purchased. it is the x5460