I noticed that the 'homepage01.jpg" image in the top left corner of your site uses a lossy file format and looks blurry compared to the other content on your homepage (especially on my 4K monitor). There are compression artifacts around the edges of the letters (giving them a noticeable blurred outline) and the colors in the logos are muted and washed out compared to the original logo graphics. I'm guessing the same JPG file was edited and saved multiple times, with each successive save throwing out more detail during compression.
Personally, I don't touch lossy file formats, such as JPG, for small graphics for this very reason and now only use PNG for these types of images - where quality is crucial. PNG will still give you a tiny file - but with the major benefit of it looking crystal clear and with no detail being lost, no matter how many times you tweak it in Paint (or whatever image editor you use) and re-save it.
So I had some time and thought I'd make a new image for you in Photoshop, using your existing one as a template - just to demonstrate the benefit of PNG over JPG. The text is nice and crisp (tried my best to match the font and the color is identical). The logos have been replaced with new downloads of current versions, so there is no degradation in image quality there. The asterisks have been replaced with actual bullet points. The width and height (400px x 140px) are also identical to your original image, so it won't break page layout if you do decide to use it to replace your old one. It just looks a bit more modern overall so it may help to give a better first impression to new visitors! The only difference between the two versions that I came up with is that the CentOS logo is different in each one.
Interestingly, the new images I made are actually half the file size of what you have at the moment, so recreating it from scratch and switching to PNG not only fixed the image quality but halved the file size.
I'm not sure if you have Photoshop but I threw in the PSD project file (with layers) so you can make adjustments - in case you want to adjust the text font or anything.
Hopefully that helps!