Planning to upgrade in or by spring 2024 - keep or replace PSU and/or case?

If the case has sufficient size and cooling for your new loads, you may keep it, but consider that with a higher end build, you may wish to treat yourself to the noise benefits of a nicer, more modern case. Also, consider that many older cases do not bring USB 3.0 headers to the front, and, vain though it may be, it is quite convenient to have a front or top mounted USB3 port for random modern flash drives and assorted external laptop drives in cases. The difference between USB2 and USB3 in transfer speeds is staggering. One may, of course, route a USB3 hub from the rear to the desktop or case top, but one often costs a substantial fraction the cost of a newer case for the same results.

I do like the noise deadening in a modern case with 120mm+ fans, and consider very strongly budgeting for a high end heat pipe based CPU cooler. In addition to running far more silently than standard AMD Prism coolers, they remove more heat, which on a modern CPU allows for higher sustained speeds. I consider most modern CPUs cooling limited until proven otherwise, and while they do not burn up with insufficient cooling, neither do they deliver full performance. A high end 7950x will benefit from a good cooler. Consider also that many smaller, older cases do not fit a modern cooler profile.

You also ought buy a new, higher power PSU than you have. Not only are you perhaps at the practical limits of your old PSU, PSUs do age and with time can no longer provide the same performance they do new - consider capacitor aging on the filter capacitors, ripple, etc. I would consider an 1000 wat PSU reasonable for your new build. A 7950 is, under proper cooling, a 200+W CPU, a 3080 series card is a 300+W card. While, in theory, a 750W PSU is sufficient to handle that, cooling, and other loads, it comes closer to the rated power than I prefer to run a PSU, especially an aged one. Perhaps a new 800W PSU, but also modern systems put more transient power demands on power supplies than older systems with the regular scaling to thermal limits as opposed to simply a standard peak power and sitting there.

I have, at more times then preferred, faught with the alchemically maddening issues caused by a power supply that is not failed, yet, is not fully functional. Everything makes some difference in system stability, yet nothing fully resolves it, components test individually OK (as they are), and the eventual "I am out of other ideas!" attempt of swapping a different PSU resolves things entirely. If budget is not sufficient, I would drop CPU or GPU cost before reusing an old PSU on a new high demand build as you're attempting.

If you buy a new case and PSU, you also keep your existing system fully functional and can sell it as a unit or reuse it as a whole system, instead of having pieces to sell separately.

Techpowerup has a nice GPU database that includes card lengths, as an example here's their RTX 4070 listing:


I'm not sure what specific GPUs you're looking at and I suspect that would change by the time you actually buy/build anyway (spring 2024 is a long ways out!) but you can probably keep an eye out for dimensions over at TechPowerUp or similar sites that do reviews/keep a database of GPUs.

Looking at your case, assuming this is it, I'd also want to measure maximum height of the card it could take (clearance to the side panel) just to be safe. A normal RTX 4070 or RTX 3080 or whatnot should be fine but if you end up shopping RTX 3090's or RTX 4090's or something, well, let's just say it would be good to check, particularly given that listed card dimensions don't consider necessary power cable clearance. Techpowerup's RTX 4090 FE review, page 3, has some great pictures comparing GTX 1080 Ti, RTX 2080 Ti, RTX 3090, and RTX 4090, as well some of AMD's recent cards.

Power supply should be upgraded if it's so old, but I'd wait til you need to as opposed to doing so in advance, especially as we're transitioning to ATX 3.0 right now - there's a decent amount of ATX 3.0 power supplies currently available but that's only going to continue to improve. ATX 3.0 in particular is much more demanding about transient power demands. i.e. as reported:

Increased tolerance for high power spikes, for the compatible PSU platforms. Up to 200% of the PSU's rated power for 100μs with a 10% duty cycle.

• Increased slew rates for transient loads (2.5 - 5x times higher for the +12V rail)

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Transient loads on modern GPUs get higher and higher so your old PCP&C unit may not be up to snuff anymore, even if it meets absolute output wattage requirements in theory. Diminished output capacity due to age is also a potential concern.

An ancillary thought: those PCP&C Silencers were not at all silent. A quality modern kilowatt supply is likely to be much quieter.

Also some things better not to reuse as they’d be beyond a reasonably expected service life (power supplies aren’t flashy and easy to forget that they’re there but I imagine they can fail after a long time.

Cases are a different matter, very personal decisions go into a case sometimes including big questions like “do I need any drives at all beyond the M.2?” or “what happens if I use water to cool my PC instead of perfectly good air?”

When you do build, please post about it afterward! I’m looking at upgrading a 5 year old PC build at some point, and when I do I’ve settled on just replacing it entirely. I’m hoping win11 makes it easy to transfer my docs and game installs over, at least to the point where steam doesn’t need to redownload everything! /wishfulthinking

malor said:

An ancillary thought: those PCP&C Silencers were not at all silent. A quality modern kilowatt supply is likely to be much quieter.

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Especially at partial load. Many modern power supplies have a feature in which, under light load, they disable the fan entirely. Some allow you to inhibit this if you rely on PSU airflow for cooling, yet, with a variety of slow turning fans, it is often possible to have a nearly silent air cooled PC under light load, that only begins making noise as demand increases.

Jeff3F said:

Also some things better not to reuse as they’d be beyond a reasonably expected service life (power supplies aren’t flashy and easy to forget that they’re there but I imagine they can fail after a long time).

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Power supplies do fail in a variety of evil ways. Some are detected and the system fails to boot as the Power Good line is never asserted. Some are only identifiable after running out of other ideas and testing hardware separately in other systems.

I would upgrade the case. In 2011, you rarely dump 400W+ of pure heat but nowadays you easily hit that with 200W for the GPU and another 150W for the CPU, and 50 for board and misc.

The new mesh front trend in cases move massive amount of air with low noise, better than earlier attempts at silencing on for example the Fractal Design Define. Works at low heat output, but gets rather loud if you need to push lots of air through small, sound proofed vents. Compare that with a Corsair Airflow case.


Some new case use vertical PCIe risers to make GPU pull on fresh cool air from the side and/or let you dump hot air out the top with a radiator slot. These things were rare even on higher end cases 10 years ago.

Definitely get a new PSU, just because of the age alone. The wattage is low for what you're planning on, but it's mostly the age.

New cases can be much more quiet and cool more efficiently than what you have now. But if that's not a concern, as long as the temps are acceptable with your new gear, I'd say keep the old one if you really like it.

I would just budget $140 more for a new case. I'll assume this is a long lone use computer. I which even after you build new and shiny it'll take you 2-3 months to figure out what you forgot and still need. Because aside from the case. Pretty much everything will be replaced.

Don't do the transfer drive and boot thing. I mean it is possible. But If you're going to do all that work. Make it count.

But if budget forces you to reuse the case. Then Buy the GPU first. That is the #1/2 component for it has to fit. Motherboards have gone away from being monsters not fitting in cases.