Show HN: I made a price aggregator to find the best PC parts deals across eBay | Hacker News Reader

Show HN: I made a price aggregator to find the best PC parts deals across eBay

pcprice.watch

20 pointstzoSkatzo16 comments

Started PC flipping as a hobby (buying used parts, building PCs, and selling them for a small profit). Found that focusing on used parts on eBay gives the best margins - like finding a GPU 20% below market, pairing it with other deals, and selling the complete build locally.

I discovered that eBay marketplaces (.com, .de, .co.uk etc.) often have different prices for the same items! Or just completely different items.

So I built an eBay price scanner for PC components. It scans listings across different Ebay markets, calculates median prices, and flags anything selling below market (including shipping costs to your location). It basically finds the best deal that is specific to your location.

It currently tracks GPUs, CPUs, RAM and motherboards across 6 eBay markets, updating every 8 hours.

Been using it myself for and it actually works!

Let me know, what you think. Would love to hear your feedback on making it more useful.

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How do you confirm that the GPU you bought from eBay is really in 100% working order? CPUs are clear case: they either boot up or they don't. If they do boot up, they are 100% ok. RAM, you do memTestx86 and it's all clear. But MBDs on the other hand ... I had ~50% failure rate from eBay where a MBD would boot up and would look like it is working correctly, only to discover that there is something somewhere that's not working as expected months later. Hence, I'm curious about your approach to GPUs.

> CPUs are clear case: they either boot up or they don't. If they do boot up, they are 100% ok.

Not necessarily. I had a Xeon once with a single bad core. It would boot fine and run for a while, but under heavy loads it would produce bad results, leading to a kernel panic due to a detected inconsistency. Disabling the defective core made the problem go away, so I eventually had the CPU replaced which fixed the issue.

I also had a Core i7 system recently that was experiencing inexplicable slowdowns while rendering video for a month or two. After replacing literally every other component in the system without resolving the problem, the CPU finally died and I was forced to replace it. The slowdowns went away immediately, so my conclusion was that the CPU was on the way out and that was causing the performance problems.

Interesting. That never happened in my experience. Which generations were those defective ones? I mean, yes, overclocking and/or overheating the CPU could damage it, but I thought Intel had every possible self-defence protection enabled in the CPU.

The defective Xeon was in a 2009 Mac Pro, so it would have been a Westmere-era processor. Even though I was certain the problem was a bad core, the guy at the Genius Bar refused to believe it was the processor. He finally grudgingly agreed to replace the processor if I really wanted, but assured me it wouldn’t solve the problem. Unsurprisingly though, it did.

The other processor was an i7-14700K, and it was about eight months old when the problems started to manifest. The processor was never overclocked, and had a pretty chunky heatsink (with no fewer than three fans) so I’m pretty sure it was never run out of spec. Intel ended up RMAing the processor without too much hassle, so I get the sense that what had happened was not entirely uncommon, and they really want to avoid any bad press relating to it.

I’m not convinced Intel’s thermal protection is all that effective these days, after reading reports of people claiming their processors have become physically warped. Apparently a popular PC mod involves replacing the “flip-down” CPU bracket with one that screws in at all four corners, supposedly to help prevent warping.

Thank you.

Yeah, the latest overvoltage scandal notwithstanding. That's a bug. Hopefully, Intel learned their lesson.

In my experience, that CPU Contact Frame mod is the best thing since sliced bread. It is obvious to me now that it should become standard on all motherboards. Mechanical benefits are numerous, but 10 degree Celsius better temperatures make it a clear winner. I installed two so far, one on 14th gen and one on 12th gen, and I'm never doing a build without one again.

Most Intel 13/14 series processors had instability flaws that caused them all to die over time. Basically every processor that was run before the fixes were finally released was likely permanently damaged.

https://www.techradar.com/computing/cpu/intel-finally-confir...

Thanks for your question.

That was a real concern of mine, for a long time. Business Wise: 1. eBay has a really good buyers protection. I've had items that were not delivered or dysfunctioning, and I got a full refund. No questions asked. 2. Make sure to check the sellers rating. - pcprice.watch also includes the sellers' rating.

But I understand that you are more asking about my approach for a GPU to work hardware-wise? Technical testing for GPUs: 1. I do PCB inspection, and I check the power connectors PCIe contracts. 2. I found out GPU-Z to be useful 3. And maybe the most telling gaming benchmark suite: 3DMark or gaming sessions

So far I haven't had any incidents that had made me lose money, and I do flip PC's quite often :)

Ah, so you are willing to tinker with it. Sure, full inspection and testing cycle could reveal if the item is 100% ok. But, in that case I'm wondering if the price difference is worth it, considering the time spent. Then we could also call it "Refurbished", no?

Technical detail for those interested:

Architecture: - Frontend: Vue.js with Tailwind CSS, hosted on Vercel - Backend: Python scripts running on Oracle Cloud VM - Data refresh: Every 8 hours via cronjob

The most interesting challenge was filtering legitimate PC part listings. eBay search isn't perfect - searching for "RTX 4090" returns lots of irrelevant items like brackets, broken cards, or water cooling kits.

I solved this using custom ML classifiers for each component type (GPU/CPU/RAM/Motherboard). Each classifier is trained on labeled eBay listings to identify legitimate parts.

This automated filtering is crucial since the scanner processes thousands of listings daily across different eBay markets and languages.

One other issue, is bypassing the eBay API limitations, since I query for thousands of items I need to somehow optimize it. So far, I'm caching useful information like Shipping, but eventually if I want to add more items and/or marketplaces, I will need to either implement a key rotation or ask ebay to extend their API limits.

Currently, I scan for around 10k eBay listings along with their shipping info.

About the search: I just did my first search for the RTX 3050, but the very first result is GTX 1660. Given that this happens all the time on eBay, and, obviously on your site as well, I think there should be a cookie-based hide-this-one-forever UI affordance and functionality to alleviate this problem.

Yeah, it's funny the eBay API tends to return mostly irrelevant listings, and I have to classify them. Even then they are like 95% accurate, one thing I could potentially improve is use a classifier per model instead of per part type.

However, your feedback is noted, I'll try to add this asap.

This is good start, i guess to make it more helpful, you can also do a pre configured builds so folks who just want to check the overal price can do that.

Also , why not do it for more things? like cellphones are hot on ebay, and i would love to use this kinda of a tool

Thanks for your feedback!

Actually I've thought of that as well, but my main concern is that it's a bit difficult to find out median prices for "non-standardized" items, and I want to offer a price comparison that is meaningful for users. So cellphones are possible, but prebuilts could be trickier. It would be an interesting challenge to tackle eventually, if eBay offers me more API calls than they currently offer.

My 2 cents: I’d call the website (top left-hand) PC Price, not PC Scanner, as the URL is pcprice.watch

Thanks for the feedback, I agree so I updated the title.

Nice site, great job.

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