_,,,^..^,,,_ said:
The XL systems was thought as HTPC, and so I think there will be no problems about HDDs heat - infact, in some models there were two, one on top of another, and I heard about no issues about HDDs heat problems, and those models are 6/7 years old... plus, newest HDDs should produce less heat than older, in particular 5900rpm models.
I was talking bigger picture; I also doubt you that would have heat problems with hard drives, but you will have an extra drive in there adding to the overall heat inside the case and taking up a bit of extra space that the air will have to spread itself out it in.
The thing that seems to affect HDD's the most is people dropping them! ;)
Yes, GPU should be low profile; in particular, the AMD based HD 5450, 6570, 6670 and 7750 are the ones tested by many XL users, and all works very well; as the PSU is only 300W, their power consumption is well under their specs, around 50/60W. Still, don't know a lot about Nvidia GT640; it's a new card for "us" XL owners, and should be tested further, but I think it will be OK, too.
PSU's usually produce less power as the capacitors age, but you'll be just fine if you leave a little bit of headroom within your 300W limit, which is a good thing to do even with a new PSU.
RAM: a heat spreader is welcome, but as the max speed is "only" 667MHz for 8GB, and 800MHz for 4GB, I don't think it will be "crucial".
Ah, you've misquoted me here. I said "crucial" in reference to your choice of graphics card. I simply said that a heat spreader is a good idea. Of course, memory at 'only' 667MHz/800MHz still gets hot, the availability of memory now clocked at 1333MHz+ doesn't mean that the old top-spec memory is going to run any cooler than it did 5 years ago.
Actually, all that said, your memory could be 'Crucial' if you wanted it to be... ;)
You might also want to try some quality thermal compound for the CPU to help heat transfer to lower the CPU temperature a few degrees; Arctic Silver 5 is pretty good for this and does work better than the standard thermal compound although the results of 'how much better' can vary, and it is a relatively inexpensive item (or so you will think until you see how small the syringe is, but there is enough for several CPU's).
I've had to repair too many systems in small form-factor cases (and laptops) that have suffered from component failure due to heat, and would rather it not happen to you, Andrea. HTPC cases are generally not high performance. A tool such as SpeedFan will help you monitor temperatures once you have performed your upgrades.
I'm sure you will have little or no trouble, but I figured I'd just give you some food for thought. It would be a shame to have any of your work disrupted by system problems; I'm really looking forward to watching your work on The Thing (when I eventually get around to getting it), and I'm hoping you'll get some more Star Wars-related work done soon.