CompUSA is a solid computer store, if you happen to have one nearby. If not , they are also TigerDirect.com. If it has to do with computer hardware, they got it... in pieces or put together. You can see what they consider a "top of the line" gaming machine VS a "budget" rig, and they have "barebones" deals that strip out a ton of stuff. If all you are looking for is a basic rig with nothing but some version of windows and EQ on it.....may be worth your time to look into it (or ask someone you trust to look them over)
As for specs... well windows will use 1-2g of ram on start up, depending on how many services and other hoopla ya got turned on/installed.
EQ will burn 1-1.5 depending on your settings and memory reduction techniques
So ( again this is just "rule of thumb" guessing, entirely depends on set up ) looking to use roughly 8-11g of ram, I would shoot for over that.
SSD are awesome but expensive (and in some cases worse then traditional) and not needed. They will help you reach the "10 second boot up" mark, but unless you want to spend some cash, not where you want your budget dollars pooled at.
Intel has been kicking the crap out of AMD for a while now in everything except price ( at least last time I got caught up on CPUs) Intel is more stable, but (depending on the chipset) you run into locking issues if you are into overclocking your rig. AMD has lower scores on most tests, but at it's cheaper price and factory tools to help overclock make it the home builders preferred chip. EQ does not utilize multiple cores... how ever MQ ( and winEQ/ISBoxer I believe) have some "round robin" core assigning set ups... it would be better to run with something with 6+ cores if you can swing it. (I am an Intel guy, but that is sorta like being a Chevy guy. AMD gets the job done at a decent price, and you wont notice the performance dip unless you are at the edges of the rig's capabilities, and generally you can get more in the AMD chip vs Intel at comparative prices....this is sorta like argueing a V8 vs a V6 engine... Intel has the horsepower and performance, AMD gets the job done, just not as milisecond fast...if you are building a budget rig , go with AMD)
Graphics... historically speaking the EQ's graphics engine occasionally has issues with ATI cards... enough so you occasionally have to juggle drivers. Nvidia has not has as many issues, and generally just has the 1 driver fits all approach. I generally have less issues with chasing down glitches/bugs with Nvidia.
https://en.wikipedia.org/wiki/List_of_Nvidia_graphics_processing_units#GeForce_900_Series
this link is maintained decently. It has a lot of technical jargon to soothe the inner geek.... the things I personally look for when shopping are the onboard VRAM, GPU, and the Bandwidth (how much information the card will push out) The more you want to spend, the better performance you can get, as usual. This is more of a "be somewhat aware" guide, since you are not building. May help with the comparison list =)
I am not much for being one to tell someone "go buy this" cause, then you are responsible when it all goes to hell =P
How ever , I will say BB does a decent job of making sure you are happy with what you are buying, and generally employ some sales guys who can answer questions intelligently. Most of them in the PC section ought to be gamers themselves, and willing to talk shop with you.
At a bare minimum, in my opinion, shoot for something with 8G+ of ram (fairly standard) with the plan to put more in as/when you can since with boxing, the more RAM the better. Shoot for something with 4+ cores, which may require you to google the CPU specs since "off the shelf" PC's don't like to advertise too many details.(at the least you can find decent spec descriptions looking up the parts at Tigerdirect.com) Dual core will work... I think someone posted elsewhere they ran 16 bots on one... but frankly the prices have come down enough that it is worth spending the money for the performance boost. And HD's are getting CHEAP, no reason to not shoot for 1t+