£100 CPU and motherboard, options (without overclocking...)

[jimbouk]

So I foolishly bought a cheap graphics card and now need to put together a budget rig for the other half. She's got a few-year-old all-in-one and it isn't too happy with the likes of Left for Dead 2 let alone anything cutting edge.

I've got myself a srubbishrubbishrubbishrubbishy looking R7870 from the classifieds, and have a m-atx case, hdd and 500W PSU kicking around and extra DDR3 RAM I can steal from my machine so I'm just short a CPU and motherboard. Money is tight so I've set aside £100 for the pair. Not interested in overclocking, I need something out of the box that works rather than needing fiddle time.

So, the best options so far seem to be:

• AMD Athlon II X4 860K FM2+ 3.7GHz 4MB Black Edition, and some FM2+ motherboard (A88X chipsets seem to start at £40)
• Some Pentium Intel Dual Core (stretch to a G3440?) and a hopefully a B85 based motherboard (or H81 if the processor is the more expensive of the dual cores).

i3s and 6 core AMD-FX chips seem to be out of reach. The other option is uber low spec AM1 CPU and motherboard for £60, though I'm not sure at what point the CPU will become a bottleneck and by how much. Aiming for 1080p.

Opinions from the cost-concious Hexites please

[smargh]

How about considering the unthinkable: a P45-based motherboard combined with the Socket 775-to-771 mod with a Xeon. The only down side is the cost of DDR2 memory, which would easily be more than the cost of the CPU, but perhaps you might have spare modules.

I did this a week ago with my Gigabyte GA-EP45-UD3P and it as improved it quite nicely. The E8400 was feeling a bit sluggish, and this should tide me over until DDR4 and USB3.1 etc are more mature in a few years time.

Comparison with G3440 and Xeon E5450: http://www.cpu-world.com/Compare/998...eon_E5450.html - the main negative seems to be lightly higher electricity usage, and the newer stuff could have significantly faster CPUs added in the future.

I just thought I'd throw this option into the mix; I know newer stuff is always the better option unless you already have old parts laying around.

Edit: I just realised that this won't satisfy your zero-fiddle-time criteria. Sorry.

[EndlessWaves]

The Pentiums are better for gaming, see Techspot's recent 860k vs. Pentium Anniversary Edition comparison: http://www.techspot.com/review/1017-...et-gaming-cpu/

The FX-4300 at £55 may be worth considering, the benchmarks here suggest the 4350 can sometimes keep up with the Pentium when the A10-7850k/860k (same CPU) can't :
http://www.techspot.com/review/849-i...ck/page13.html

The G3440 is old stock and overpriced. The G3250 (3.2Ghz), G3450(3.5Ghz) and G3460(3.6Ghz) currently seem to be the best prices:
http://www.ebuyer.com/658396-intel-p...r-bx80646g3250
http://www.dabs.com/products/intel-p...-3mb-9D9Q.html
http://www.ebuyer.com/641560-intel-p...l-bx80646g3450
http://www.novatech.co.uk/products/c...n=PCPartPicker

Comparison with G3440 and Xeon E5450: http://www.cpu-world.com/Compare/998...eon_E5450.html - the main negative seems to be lightly higher electricity usage, and the newer stuff could have significantly faster CPUs added in the future.

They're completely different architectures, you can't compare them like that. The E5450 is very similar to the Core 2 Quad Q9650 and there are some game benchmarks comparing the Q9650 and Haswell Celeron/Pentium models here:
http://www.techspot.com/article/1039...red/page5.html

Best case is that it can keep up with a £28 CPU, worst case is half the speed. Power consumption is a LOT higher.

If you wanted to go second hand then a Sandy Bridge i5 would be the best choice, the cheapest systems go for around £100 on ebay.

[CAT-THE-FIFTH]

The only problem is that Techspot don't test intensive sequences and more importantly they don't test frametimes - the Pentium dual cores can stutter in some more modern titles. Plus with DX12 incoming,I don't see the Pentium dual cores as being more than stop-gap CPUs although the platform has better upgrade potential than AM3+ or FM2+ IMHO.

Regarding the AM3+ route,this is what I would get:

http://www.cclonline.com/product/934...e-CPU/CPU0156/
http://www.cclonline.com/product/146...-1-0-/MBD1317/

If you are willing to spend a few quid more,you could fit in a Core i3:

http://www.ebuyer.com/658398-intel-c...-bx80646i34160
http://www.ebuyer.com/662745-asrock-...ro-h81m-dgs-r2

[EndlessWaves]

The only problem is that Techspot don't test intensive sequences and more importantly they don't test frametimes - the Pentium dual cores can stutter in some more modern titles.

Then link to someone who does, preferably also with a test of a (full) quad core of similar overall speed to show that it is a core count issue rather than a performance one.

I'm no expert on CPU architecture and multi-threaded programming but from what I do know it seems improbable.

[DanceswithUnix]

Then link to someone who does, preferably also with a test of a (full) quad core of similar overall speed to show that it is a core count issue rather than a performance one.

I'm no expert on CPU architecture and multi-threaded programming but from what I do know it seems improbable.

Try this:

If you try and squeeze lots of threads onto not enough cores, then there is a tendency for threads that would have stayed on a core to end up running on a different core. That has a high cost, as the instructions and data for that thread has to be moved into the cache of the other core which is as good as turning the cache off in terms of performance. So you get hit twice, just at the point that the system is hurting enough that it makes bad guesses where to run work, most of the precious CPU cache stops working well.

Note that this scenario is an interaction with the OS scheduler tuning (it hit the FX8150 badly on launch despite having enough cores) hence an i3 with 4 threads on those 2 cores can make the world of difference because it makes life easier for Windows to allocate work to cores thanks to those extra threads, and it doesn't guess wrong so often.

Have a look at this Thief graph, the i3 is stuttering way less than a overclocked Pentium http://www.tomshardware.com/reviews/...ng,3888-4.html

http://www.tomshardware.com/reviews/...ng,3888-4.html

[jimbouk]

Cheers for the input everyone. I think even with the 'only dual core' limitations of the Pentium chips, for the money they're going to give best bang for buck - especially if I keep an eye on the classifieds in a year or so and have the potential to drop in an i5. I'm currently running an FX-6300 myself which I'm very happy with and have been an AMD purchaser for a while so this is a brave new world for me!

I'm going to dig the old case out the loft at the weekend - I remember it being fairly tight around the edges which puts me off mATX boards with SATA ports pointing sideways off the edge.

B85 worth the money over H81 in terms of chipsets or should I just pick the best looking board in terms of ports and layout? With the processor coming in the low £50s there's some wiggle room there.

[jimbouk]

So I splashed out just under £84 at the weekend on a Intel Pentium Dual Core G3258 and MSI H81M-P33. Going against my original requirement I might give a mild overclock a go so went for the Anniversary edition, a quick google showed the MSI H81M-P33 to be a sensible option for this. Maybe do a few pictures of assembly - the R7870 is a rediculus size for the case I've got and I'm going to be using a spaghetti of power cables to get it all rigged up - joy!

[jels]

If you don't mind 2nd hand I wold keep an eye on ebay ect, I picked up a i5-3570 (3.4 GHz Quad-Core) with a asus z77 board for £100 last week.