I've a passively cooled undervolted & overclocked A6-3500 in a Streacom F5C case and I'm going to be adding a single slot AFOX HD 7850. I'm just wondering whether the CPU will significantly bottleneck the GPU in this configuration? If so what is the best FM1 socket cpu under these conditions? or should I just throw out the MB and go with a 3220T.

I can overclock the CPU a lot further (>3.3GHz) however I'm reaching the thermal limit @1.15-1.20V in IBT after 5-10 runs. Is this typical for my configuration or have I messed up the cooling some how (heat pipes punctured)? I find it a bit surprising because the a6-3500 runs 1.415V default Vcore. It doesn't overheat in normal HTPC operation (XBMC), but I'm guessing gaming will push it alot further.

CPU: AMD a6-3500@1.15VCORE, 135x21 = 2.8 GHz
Case: Streacom f5c
MB: ASUS F1A75-M LE
PSU: Wesena PicoPSU

BTW I know there are significant issues with adding a discrete GPU to the case (I'm planning dual pico-psu and possibly modifying the case to vent gpu exhaust).

CPU bottleneck: depends on the games, resolution, and quality settings.

More importantly, adding 100W+ of heat to this case might not work out and this single slot card is also pretty noisy....

Yup, totally agreed. No way this case will be able to handle that kind of heat. You might have a ghost of a chance if you came up with customized heatblock to the GPU & nicely designed heatpipies w/ good connection to the unused side heatsink... but even then, it'd be iffy.

Gaming at 1080P, mostly console ports.

I'm pretty sure it will work if I directly vent the GPU exhaust out the top.... I'm going to make a plastic adaptor which directs the flow from the cooler so it doesn't end up in the case. There's intake holes pretty close by aswell, I may move the GPU so it fits directly over them. Worse come to worse I should be able to undervolt / clock the GPU. The noise is an issue, but I can turn the GPU off in the bios when its not needed if its really bad. I might hang it from the roof of the case with rubber, see if it helps. I also was thinking of modifying a Accelero Mono PLUS.

Console ports aren't known to be very taxing, so you might be ok. If not, the i3-3220 certainly can run rings around your A6. Don't bother with the T part.

Good luck with the gpu cooling.

Well I've installed the GPU. Everything works fine. I've two 12V power supplies, a 120W going to the picopsu and another 192W is directly wired to the PCI-E power connector and PCI-E bus extender for the gpu. I haven't done any case mods to improve airflow yet.

Giant mess of wires, Foam pads are just placeholders for now:


Custom backplate. You can see the GPU has been shifted ~5cm to the right so I don't have access to the other ports:


I've set a custom fan profile in MSI Afterburner so the the fan is off when less than 60C then ramps up to 70% at 90C (anything above is 100% fan). The fan is off during normal HTPC workloads. I played Dishonored for about an hour today and reach a max temp of 79C (fanspeed = ~50%). IMO this fan noise is fine while gaming. It managed to maintain 60fps@1080P with all settings high, but i guess this game is fairly cpu light (I wasn't OC-ing CPU either).

One issue with the AFOX 7850 is I can't seem to change the vcore voltage or set the core / mem clockspeeds lower than 300/150. I'm guessing this is a software issue.